Upstart (UPST) 10-Q 7 Nov 23 2023 Q3 Quarterly report Financial data

Cover

Cover - shares	9 Months Ended
	Sep. 30, 2023	Nov. 01, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	001-39797
Entity Registrant Name	Upstart Holdings, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-4332431
Entity Address, Address Line One	2950 S. Delaware Street
Entity Address, Address Line Two	Suite 410
Entity Address, City or Town	San Mateo
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94403
City Area Code	833
Local Phone Number	212-2461
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	UPST
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		85,057,317
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001647639
Current Fiscal Year End Date	--12-31

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($)		Sep. 30, 2023	Dec. 31, 2022
Assets
Cash		$ 516,581,000	$ 422,411,000
Restricted cash		98,447,000	110,056,000
Loans (at fair value)	[1]	972,336,000	1,010,421,000
Property, equipment, and software, net		48,010,000	44,168,000
Operating lease right of use assets		77,339,000	86,335,000
Beneficial interests (at fair value)		36,974,000	0
Non-marketable equity securities		41,250,000	41,250,000
Goodwill		67,062,000	67,062,000
Other assets (includes $42,648 and $42,673 at fair value as of December 31, 2022 and September 30, 2023, respectively)		143,780,000	154,351,000
Total assets	[2]	2,001,779,000	1,936,054,000
Liabilities:
Accounts payable		7,027,000	18,715,000
Payable to investors		51,607,000	90,777,000
Borrowings		1,003,392,000	986,394,000
Payable to securitization note holders (at fair value)		153,782,000	0
Accrued expenses and other liabilities (includes $8,820 and $7,414 at fair value as of December 31, 2022 and September 30, 2023, respectively)		51,853,000	66,946,000
Operating lease liabilities		93,354,000	100,787,000
Total liabilities	[2]	1,361,015,000	1,263,619,000
Stockholders’ equity:
Common stock, $0.0001 par value; 700,000,000 shares authorized; 81,259,676 and 85,024,889 shares issued and outstanding as of December 31, 2022 and September 30, 2023, respectively		9,000	8,000
Additional paid-in capital		880,933,000	714,871,000
Accumulated deficit		(240,178,000)	(42,444,000)
Total stockholders’ equity		640,764,000	672,435,000
Total liabilities and stockholders’ equity		$ 2,001,779,000	$ 1,936,054,000
[1] Includes $196.5 million as of September 30, 2023 of loans, at fair value, contributed as collateral for the consolidated securitization. Refer to “ Note 6. Fair Value Measurement ” for details. December 31, September 30, 2022 2023 Assets Cash $ 838 $ 762 Restricted cash 13,147 23,888 Loans (at fair value) 958,822 964,917 Other assets (includes $2,244 and $10,051 at fair value as of December 31, 2022 and September 30, 2023, respectively) 11,674 11,218 Total assets $ 984,481 $ 1,000,785 Liabilities Payable to investors $ — $ 1,216 Borrowings 336,452 351,169 Payable to securitization note holders (at fair value) — 153,782 Accrued expenses and other liabilities 1,378 1,887 Total liabilities 337,830 508,054 Total net assets $ 646,651 $ 492,731

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands		Sep. 30, 2023	Dec. 31, 2022
Other assets at fair value		$ 42,673	$ 42,648
Accrued expenses and other liabilities at fair value		$ 7,414	$ 8,820
Common stock, par value (in dollars per share)		$ 0.0001	$ 0.0001
Common stock, authorized (in shares)		700,000,000	700,000,000
Common stock, issued (in shares)		85,024,889	81,259,676
Common stock, outstanding (in shares)		85,024,889	81,259,676
Loans held in consolidated securitization		$ 196,500
Assets
Cash		516,581	$ 422,411
Restricted cash		98,447	110,056
Loans (at fair value)	[1]	972,336	1,010,421
Other assets (includes $2,244 and $10,051 at fair value as of December 31, 2022 and September 30, 2023, respectively)		143,780	154,351
Total assets	[2]	2,001,779	1,936,054
Liabilities
Payable to investors		51,607	90,777
Borrowings		1,003,392	986,394
Payable to securitization note holders (at fair value)		153,782	0
Accrued expenses and other liabilities		51,853	66,946
Total liabilities	[2]	1,361,015	1,263,619
Total stockholders’ equity		640,764	672,435
Variable Interest Entity, Primary Beneficiary
Other assets at fair value		10,051	2,244
Assets
Cash		762	838
Restricted cash		23,888	13,147
Loans (at fair value)		964,917	958,822
Other assets (includes $2,244 and $10,051 at fair value as of December 31, 2022 and September 30, 2023, respectively)		11,218	11,674
Total assets		1,000,785	984,481
Liabilities
Payable to investors		1,216	0
Borrowings		351,169	336,452
Payable to securitization note holders (at fair value)		153,782	0
Accrued expenses and other liabilities		1,887	1,378
Total liabilities		508,054	337,830
Total stockholders’ equity		$ 492,731	$ 646,651
[1] Includes $196.5 million as of September 30, 2023 of loans, at fair value, contributed as collateral for the consolidated securitization. Refer to “ Note 6. Fair Value Measurement ” for details. December 31, September 30, 2022 2023 Assets Cash $ 838 $ 762 Restricted cash 13,147 23,888 Loans (at fair value) 958,822 964,917 Other assets (includes $2,244 and $10,051 at fair value as of December 31, 2022 and September 30, 2023, respectively) 11,674 11,218 Total assets $ 984,481 $ 1,000,785 Liabilities Payable to investors $ — $ 1,216 Borrowings 336,452 351,169 Payable to securitization note holders (at fair value) — 153,782 Accrued expenses and other liabilities 1,378 1,887 Total liabilities 337,830 508,054 Total net assets $ 646,651 $ 492,731

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenue:
Revenue from fees, net		$ 146,755	$ 179,348	$ 407,585	$ 751,675
Interest income and fair value adjustments, net:
Interest income	[1]	37,692	22,180	116,923	66,288
Interest expense	[1]	(9,414)	(3,050)	(20,828)	(6,322)
Fair value and other adjustments	[1]	(40,476)	(41,245)	(130,430)	(116,110)
Total interest income and fair value adjustments, net		(12,198)	(22,115)	(34,335)	(56,144)
Total revenue		134,557	157,233	373,250	695,531
Operating expenses:
Sales and marketing		33,042	56,362	88,371	295,023
Customer operations		36,914	45,028	114,301	144,507
Engineering and product development		54,941	66,182	222,986	173,218
General, administrative, and other		53,505	47,752	156,616	138,148
Total operating expenses		178,402	215,324	582,274	750,896
Loss from operations		(43,845)	(58,091)	(209,024)	(55,365)
Other income, net		3,540	1,880	11,334	2,018
Net loss before income taxes		(40,305)	(56,211)	(197,690)	(53,347)
Provision for income taxes		10	12	44	55
Net loss		$ (40,315)	$ (56,223)	$ (197,734)	$ (53,402)
Net loss per share, basic (in dollars per share)		$ (0.48)	$ (0.69)	$ (2.38)	$ (0.64)
Net loss per share, diluted (in dollars per share)		$ (0.48)	$ (0.69)	$ (2.38)	$ (0.64)
Weighted-average number of shares outstanding used in computing net loss per share, basic (in shares)		84,404,966	81,672,099	83,158,146	83,236,131
Weighted-average number of shares outstanding used in computing net loss per share, diluted (in shares)		84,404,966	81,672,099	83,158,146	83,236,131
[1] Balances for three and nine months ended September 30, 2023 include amounts related to the consolidated securitization. Refer to “ Note 2. Revenue ” for details.

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings (Accumulated Deficit)
Beginning balance (in shares) at Dec. 31, 2021		83,659,665
Beginning balance at Dec. 31, 2021	$ 807,078	$ 8	$ 740,849	$ 66,221
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		2,074,763
Issuance of common stock upon exercise of stock options	10,726	$ 1	10,725
Issuance of common stock upon settlement of restricted stock units (in shares)		179,559
Issuance of common stock upon settlement of restricted stock units	(8)		(8)
Shares withheld related to net share settlement of restricted stock units (in shares)		(188,726)
Stock-based compensation expense	96,582		96,582
Issuance of common stock under employee stock purchase plan (in shares)		162,796
Issuance of common stock under employee stock purchase plan	7,662		7,662
Repurchases of stock (in shares)		(4,434,331)
Repurchases of stock	(150,070)	$ (1)	(150,069)
Net loss	(53,402)			(53,402)
Ending balance (in shares) at Sep. 30, 2022		81,831,178
Ending balance at Sep. 30, 2022	718,568	$ 8	705,741	12,819
Beginning balance (in shares) at Jun. 30, 2022		82,188,372
Beginning balance at Jun. 30, 2022	757,071	$ 8	688,021	69,042
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		270,390
Issuance of common stock upon exercise of stock options	1,319		1,319
Issuance of common stock upon settlement of restricted stock units (in shares)		(319)
Issuance of common stock upon settlement of restricted stock units	(8)		(8)
Shares withheld related to net share settlement of restricted stock units (in shares)		(188,726)
Stock-based compensation expense	38,206		38,206
Issuance of common stock under employee stock purchase plan (in shares)		114,902
Issuance of common stock under employee stock purchase plan	3,231		3,231
Repurchases of stock (in shares)		(930,893)
Repurchases of stock	(25,028)		(25,028)
Net loss	(56,223)			(56,223)
Ending balance (in shares) at Sep. 30, 2022		81,831,178
Ending balance at Sep. 30, 2022	$ 718,568	$ 8	705,741	12,819
Beginning balance (in shares) at Dec. 31, 2022	81,259,676	81,259,676
Beginning balance at Dec. 31, 2022	$ 672,435	$ 8	714,871	(42,444)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)	1,058,804	1,058,804
Issuance of common stock upon exercise of stock options	$ 9,475	$ 1	9,474
Issuance of common stock upon settlement of restricted stock units (in shares)		2,247,325
Shares withheld related to net share settlement of restricted stock units (in shares)		(375)
Shares withheld related to net share settlement of restricted stock units	(6)		(6)
Stock-based compensation expense	148,163		148,163
Issuance of common stock under employee stock purchase plan (in shares)		459,459
Issuance of common stock under employee stock purchase plan	8,431		8,431
Net loss	$ (197,734)			(197,734)
Ending balance (in shares) at Sep. 30, 2023	85,024,889	85,024,889
Ending balance at Sep. 30, 2023	$ 640,764	$ 9	880,933	(240,178)
Beginning balance (in shares) at Jun. 30, 2023		83,811,484
Beginning balance at Jun. 30, 2023	638,145	$ 8	838,000	(199,863)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		288,111
Issuance of common stock upon exercise of stock options	2,803	$ 1	2,802
Issuance of common stock upon settlement of restricted stock units (in shares)		777,969
Stock-based compensation expense	37,428		37,428
Issuance of common stock under employee stock purchase plan (in shares)		147,325
Issuance of common stock under employee stock purchase plan	2,703		2,703
Net loss	$ (40,315)			(40,315)
Ending balance (in shares) at Sep. 30, 2023	85,024,889	85,024,889
Ending balance at Sep. 30, 2023	$ 640,764	$ 9	$ 880,933	$ (240,178)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities
Net loss	$ (197,734)	$ (53,402)
Adjustments to reconcile net loss to net cash used in operating activities:
Change in fair value of financial instruments	151,317	71,056
Stock-based compensation	142,273	92,035
Gain on loan servicing arrangement, net	(10,432)	(23,770)
Depreciation and amortization	15,800	9,859
Non-cash interest expense	2,296	2,294
Other	(2,260)	0
Net changes in operating assets and liabilities:
Purchase of loans held-for-sale	(2,076,734)	(6,978,644)
Proceeds from sale of loans held-for-sale	1,875,358	6,374,107
Principal payments received for loans held-for-sale	139,582	104,049
Principal payments received for loans held by consolidated securitization	12,302	0
Other assets	27	8,719
Operating lease liability and right-of-use asset	1,563	7,695
Accounts payable	(11,699)	3,446
Payable to investors	(44,919)	(13,754)
Accrued expenses and other liabilities	(13,521)	(25,494)
Net cash used in operating activities	(16,781)	(421,804)
Cash flows from investing activities
Purchase of loans held-for-investment	(121,294)	(55,294)
Proceeds from sale of loans held-for-investment	774	11,993
Principal payments received for loans held-for-investment	78,327	27,711
Principal payments received for notes receivable and repayments of residual certificates	3,556	5,508
Acquisition of beneficial interests	(39,505)	0
Purchase of non-marketable equity securities	0	(1,000)
Purchase of property and equipment	(1,285)	(7,088)
Capitalized software costs	(9,135)	(10,842)
Net cash used in investing activities	(88,562)	(29,012)
Cash flows from financing activities
Payments made on securitization notes	(10,016)	0
Proceeds from issuance of securitization notes	165,318	0
Proceeds from borrowings	529,494	430,270
Repayments of borrowings	(514,792)	(209,079)
Proceeds from issuance of common stock under employee stock purchase plan	8,431	7,662
Proceeds from exercise of stock options	9,475	10,726
Taxes paid related to net share settlement of equity awards	(6)	(8)
Repurchases of common stock	0	(150,070)
Net cash provided by financing activities	187,904	89,501
Change in cash and restricted cash	82,561	(361,315)
Cash and restricted cash at beginning of period	532,467	1,191,241
Cash and restricted cash at end of period	615,028	829,926
Supplemental disclosures of cash flow information
Cash paid for interest	22,481	7,952
Cash (received) paid for income taxes, net	(982)	206
Supplemental disclosures of non-cash investing and financing activities
Securities retained under consolidated securitization transaction	44,763	0
Beneficial interests included in payable to investors	5,749	0
Capitalized stock-based compensation expense	5,890	4,547
Cash and Restricted Cash
Cash	516,581
Restricted cash	98,447
Total cash and restricted cash	$ 615,028	$ 829,926

Description of Business and Sig

Description of Business and Significant Accounting Policies	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Description of Business and Significant Accounting Policies	Description of Business and Significant Accounting Policies Description of Business Upstart Holdings, Inc. and its subsidiaries (together “Upstart”, the “Company”, “we”, or “our”) apply artificial intelligence models and cloud applications to the process of originating consumer credit. The Company helps originate credit by providing lending partners with access to a proprietary, cloud-based, artificial intelligence lending marketplace. As the Company’s technology continues to improve and additional lending partners adopt the Upstart platform, consumers benefit from improved access to affordable and frictionless credit. The Company currently operates in the United States and is headquartered in San Mateo, California and Columbus, Ohio. The Company’s fiscal year ends on December 31. Basis of Presentation and Consolidation The accompanying unaudited condensed consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements included in our Annual Report on Form 10-K. Certain prior period amounts have been reclassified or disaggregated where appropriate to conform to the current period presentation of such amounts. In the opinion of management, the accompanying condensed consolidated financial statements reflect all adjustments, which include only normal recurring adjustments, necessary to state fairly the Company’s financial position, results of operations, comprehensive loss and cash flows for the periods presented, but are not necessarily indicative of the results of operations to be anticipated of any future annual or interim periods. Certain information and disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to rules and regulations of the Securities and Exchange Commission. Accordingly, the information included in this Quarterly Report on Form 10-Q should be read in conjunction with the consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K for the year ended December 31, 2022. Use of Estimates The preparation of the unaudited condensed consolidated financial statements in conformity with GAAP requires that management make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. Significant estimates and assumptions made in the accompanying condensed consolidated financial statements, which Management believes are critical in understanding and evaluating the Company’s reported financial results include: (i) fair value determinations; (ii) stock-based compensation; (iii) consolidation of VIEs; and (iv) the evaluation for impairment of goodwill. The Company bases its estimates on various factors it believes to be reasonable under the circumstances. Actual results could differ from those estimates and such differences could affect the results of operations reported in future periods. Derivative Financial Instruments The Company evaluates its contracts and financial instruments to determine if these contracts and instruments or their parts meet the definition of derivatives in accordance with the requirements of the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 815, Derivatives and Hedging . Derivatives are recorded on the condensed consolidated balance sheets at fair value with changes in the value recorded in earnings on the condensed consolidated statements of operations and comprehensive loss, and are reported within the net cash used in operating activities in the condensed consolidated statements of cash flows. The Company uses derivative instruments to manage risks related to our ongoing business operations, including managing interest rates on our warehouse facilities. The Company does not employ derivatives for trading or speculative purposes and has no derivatives classified as accounting hedges. Refer to “Note 4. Derivative Financial Instruments” for additional information. Beneficial Interests Beneficial interests represent the Company’s right to receive or an obligation to make cash payments to certain loan buyers based on the performance of credit losses of the underlying loan portfolios. The Company evaluates these arrangements to determine if they or their components meet the characteristics of derivative instruments. Beneficial interests that meet such characteristics are reported in accordance with the derivative financial instruments policy. For other beneficial interests that meet the criteria of a debt security, the Company has elected to record the arrangement at fair value and recognize the changes in fair value and other adjustments on the condensed consolidated statements of operations and comprehensive loss. Refer to “Note 5. Beneficial Interests” for additional information. Consolidated Securitization The Company elected the measurement alternative under ASC 810, Consolidation , and maximizes the use of observable inputs to estimate the fair value of the financial assets and liabilities of a consolidated securitization entity. Under the measurement alternative, the Company determined that the fair value of the liabilities, which consists of securitization notes and residual certificates issued by the entity, is based on more observable inputs than inputs used to determine the fair value of the assets, which consists of held-for-sale loans. Thus, the fair value of these loans is determined by the sum of the fair value of the related securitization notes and residual certificates. Changes in the fair value of these assets and liabilities are included in the consolidated statements of operations and comprehensive loss. See “ Note 3. Variable Interest Entities ” and “ Note 6. Fair Value Measurement ” for additional information. Recently Adopted Accounting Pronouncements On January 1, 2023, the Company adopted Accounting Standards Update (“ASU”) 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers, which was issued by the FASB in October 2021. The new guidance requires contract assets and contract liabilities acquired in a business combination to be recognized and measured by the acquirer on the acquisition date in accordance with ASC 606 , Revenue from Contracts with Customers , as if it had originated the contracts. Under the previous business combinations guidance, such assets and liabilities are recognized by the acquirer at fair value on the acquisition date. The ASU will be applied prospectively to business combinations occurring after the adoption date. The adoption of this new standard did not have an impact on the Company's condensed consolidated financial statements or related disclosures. Recently Issued Accounting Pronouncements In October 2023, the FASB issued ASU 2023-06, Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative (the “Update”) . The amendments in this Update clarify or improve current disclosure and presentation requirements of a variety of topics, including ASC 230-10, Statement of Cash Flows , ASC 260-10, Earnings Per Share , ASC 470-10, Debt , and ASC 815-10, Derivatives, and are intended to align requirements under GAAP with those under Regulation S-X or Regulation S-K. The effective date for each amendment in the Update will be the date on which the SEC’s removal of that related disclosure from Regulation S-X or Regulation S-K becomes effective. However, if by June 30, 2027, the SEC has not removed the applicable requirements from Regulation S-X or Regulation S-K, the amendments will not be effective for any entities. Early adoption is prohibited and the amendments should be applied prospectively. The

Revenue

Revenue	9 Months Ended
	Sep. 30, 2023
Revenue from Contract with Customer [Abstract]
Revenue	Revenue Revenue from Fees, Net The Company disaggregates revenue from fees by type of service for the periods presented as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Revenue from fees, net: Platform and referral fees, net $ 134,786 $ 112,437 $ 618,208 $ 295,859 Servicing and other fees, net 44,562 34,318 133,467 111,726 Total revenue from fees, net $ 179,348 $ 146,755 $ 751,675 $ 407,585 Platform and Referral Fees, Net The Company enters into contracts with lending partners to provide access to a cloud-based artificial intelligence lending marketplace developed by the Company (the “Upstart platform”) to enable lending partners to originate unsecured personal and secured auto loans. The Upstart platform includes a cloud-based application (through Upstart.com or a lending partner-branded program) for submitting loan applications, verifying information provided within submitted applications, risk underwriting (through a series of proprietary technology solutions), delivery of electronic loan offers, and if the offer is accepted by the borrower, electronic loan documentation signed by the borrower. Lending partners can specify certain parameters of loans they are willing to originate. Under these contracts, lending partners can choose to use Upstart’s referral services, which allow them to access new borrowers through Upstart’s marketing channels. After origination, Upstart-powered loans are either retained by lending partners, purchased by the Company for immediate resale to institutional investors under loan sale agreements, or purchased and held by the Company. For loans purchased by the Company, Upstart pays lending partners a one-time loan premium fee upon completion of the minimum contractual holding period. Upstart also pays lending partners monthly loan trailing fees based on the amount and timing of principal and interest payments made by borrowers of the underlying loans. Both the loan premium fees and loan trailing fees are consideration payable to customers, which are our lending partners, and are recorded as a reduction to platform and referral fees, net, which is part of revenue from fees, net, in the condensed consolidated statements of operations and comprehensive loss. The Company recognized $6.1 million and $20.9 million of loan premium fees and loan trailing fees as contra-revenue within platform and referral fees, net during the three and nine months ended September 30, 2022, respectively, and $2.2 million and $5.6 million during the three and nine months ended September 30, 2023, respectively. As of December 31, 2022 and September 30, 2023, the Company recognized $4.9 million and $4.2 million of loan trailing fee liability, respectively, which is recorded at fair value and included within accrued expenses and other liabilities on the Company’s condensed consolidated balance sheets. Refer to “ Note 6. Fair Value Measurement ” for additional information on changes in fair value associated with trailing fee liabilities. The Company’s arrangements for platform and referral services typically consist of an obligation to provide one or both of these services to customers, on a when and if needed basis (a stand-ready obligation), and revenue is recognized as such services are performed. Additionally, the services have the same pattern and period of transfer, and when provided individually or together, are accounted for as a single combined performance obligation representing a series of distinct services. Platform and referral services are typically provided under a fixed or variable price per unit based on a percentage of the value of loans originated each period with certain lending partners subject to minimum fees; however, pricing for these services may also be based on usage fees, calculated as a percentage of each loan originated. The nature of the Company’s promise is to stand-ready and provide continuous access to and process transactions through the platform. Platform and referral fees represent variable consideration as loan origination volume is not known at contract inception. These fees are determined each time a loan is originated. Fees for platform and referral services are typically billed and paid on either a daily or monthly basis. As such, the Company’s contracts with customers do not include a significant financing component. The Company had $31.1 million and $19.8 million of accounts receivable that are included in other assets on the condensed consolidated balance sheets related to contracts with customers as of December 31, 2022 and September 30, 2023, respectively. The standard payment terms on accounts receivable are 30 days. The Company’s allowance for bad debt and bad debt expense were immaterial for the periods presented. The Company capitalizes incremental costs of obtaining a contract with a customer, which are certain sales commissions paid to employees in connection with the acquisition of lending partners. Capitalized costs are amortized over the expected period of benefit, which we have determined, based on an analysis, to be three years. The Company applies the practical expedient to expense costs to obtain contracts with customers if the amortization period is one year or less. As of December 31, 2022 and September 30, 2023, the Company had a $2.6 million and $2.7 million amount of contract costs, respectively, capitalized within other assets on the condensed consolidated balance sheets. The Company amortized an immaterial amount of capitalized contracts costs to sales and marketing in the condensed consolidated statements of operations and comprehensive loss for the periods presented. Customers accounting for greater than 10% of total revenue were as follows: Three Months Ended Nine Months Ended September 30, 2022 2023 2022 2023 Customer A 45% 33% 47% 30% Customer B 26% 32% 29% 31% Customer C * 12% * 11% * Less than 10% Customers accounting for greater than 10% of accounts receivable were as follows: December 31, September 30, 2022 2023 Customer C 27% 15% Servicing and Other Fees, Net The Company also enters into contracts with lending partners and institutional investors to provide loan servicing for the life of Upstart-powered loans. These services commence upon origination of these loans by lending partners and include collection, processing and reconciliations of payments received, institutional investor reporting and borrower customer support as well as distribution of funds to the holders of the loans. The Company charges the loan holder a monthly servicing fee calculated based on a predetermined percentage of the outstanding principal balance. Servicing fees also include certain ancillary fees charged on a per transaction basis for processing late payments and payments declined due to insufficient funds. Servicing fees are recognized in the period the services are provided. Loan servicing fees are not within the scope of ASC 606 and are accounted for under ASC 860, Transfers and Servicing . Servicing and other fees, net also include gains and losses on assets and liabilities recognized under loan servicing arrangements for loans retained by lending partners or loans sold to institutional investors. Such gains or losses are recognized based on whether the benefits of servicing are expected to be more or less than adequate compensation for servicing obligations performed by the Company. Servicing fees also include changes in fair value of loan servicing assets and liabilities in the periods presented. Refer to “ Note 6. Fair Value Measurement ” for additional information on changes in fair value associated with servicing assets and liabilities. The Company recognized a net gain related to loan servicing rights upon loan sales for the periods presented as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Net gain related to loan servicing rights $ 6,038 $ 3,472 $ 23,770 $ 10,432 The Company charges lending partners and institutional investors for collection agency fees related to their outstanding loan portfolio. The Company either performs borrower collection activities in-house, or outsources to third-party collection agencies particularly for loans that are more than 30 days past due or charged off. The Company has discretion in hiring the collection agencies and determining the scope of their work. As the principal in the arrangement, the Company recognizes gross revenue from collection agency fees in the period that the services are provided. Upstart also receives certain ancillary borrower fees inclusive of late payment fees and ACH fail fees. Revenue from collection agency fees and borrower fees are included in servicing and other fees, net as part of revenue from fees, net in the Company’s condensed consolidated statements of operations and comprehensive loss. The total fees charged by collection agencies are also recognized in the period incurred and reported as part of customer operations expenses. The Company recognized collection agency fees and borrower fees, which are included in servicing and other fees, net for the periods presented as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Collection agency fees $ 2,790 $ 4,017 $ 7,345 $ 11,685 Borrower fees $ 7,005 $ 7,182 $ 18,125 $ 21,823 Interest Income and Fair Value Adjustments, Net Interest income and fair value adjustments, net is comprised of interest income, interest expense and net changes in the fair value of financial instruments, held in the Company’s normal course of business at fair value, including derivatives, beneficial interests, loans and notes receivable and residual certificates. The following table presents components of the interest income and fair value adjustments, net presented in the Company’s condensed consolidated statements of operations and comprehensive loss: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Interest income (1) $ 22,180 $ 37,692 $ 66,288 $ 116,923 Interest expense (1) (3,050) (9,414) (6,322) (20,828) Fair value and other adjustments Unrealized loss, charge-offs, and other adjustments, net (20,069) (37,521) (70,855) (108,175) Realized loss on sale of loans, net (21,176) (2,955) (45,255) (22,255) Total fair value and other adjustments, net (1) (41,245) (40,476) (116,110) (130,430) Total interest income and fair value adjustments, net $ (22,115) $ (12,198) $ (56,144) $ (34,335) (1) Includes interest income, interest expense and fair value adjustments, net related to the consolidated securitization as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Interest income and fair value adjustments, net related to consolidated securitization: Interest income $ — $ 10,048 $ — $ 10,048 Interest expense — (3,754) — (3,754) Fair value and other adjustments Unrealized gain, charge-offs, and other adjustments, net — 367 — 367 Realized loss on sale of loans, net — — — — Total fair value and other adjustments, net — 367 — 367 Total interest income and fair value adjustments, net $ — $ 6,661 $ — $ 6,661 Interest Income Interest income is recognized based on the terms of the underlying agreements with borrowers for loans held on the Company’s condensed consolidated balance sheets and is earned over the life of a loan. Interest income also includes accrued interest earned on outstanding loans but not collected. Loans that have reached a delinquency of over 120 days are classified as non-accrual status and any accrued interest recorded in relation to these loans is reversed in the respective period. The Company does not record an allowance for credit losses on accrued interest receivable. As of December 31, 2022 and September 30, 2023, the Company has recorded $12.8 million and $12.0 million of accrued interest income in loans on the condensed consolidated balance sheets, respectively. Interest Expense Interest expense is primarily related to interest recorded on the Company’s borrowings on warehouse credit facilities, and interest expense related to the consolidated securitization. Interest expense includes accrued interest incurred but not paid. Accrued interest expenses were immaterial as of December 31, 2022 and September 30, 2023. Interest expense also includes changes in fair value of the interest rate cap. Refer to “ Note 4. Derivative Financial Instruments ” for additional information. Fair Value and Other Adjustments, Net Fair value and other adjustments, net include changes in fair value of financial instruments, other than loan servicing assets and liabilities and the interest rate cap. These adjustments are recorded in the Company’s condensed consolidated statements of operations and comprehensive loss and include both realized and unrealized changes to the value of related assets and liabilities. Refer to “ Note 6. Fair Value Measurement ” for additional information.

Variable Interest Entities

Variable Interest Entities	9 Months Ended
	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Variable Interest Entities	Variable Interest Entities Consolidated VIEs The Company consolidates variable interest entities (“VIEs”) in which the Company has a variable interest and is determined to be the primary beneficiary. This determination is based on whether the Company has a variable interest (or combination of variable interests) that provides the Company with (a) the power to direct the activities that most significantly impact the VIE’s economic performance and (b) the obligation to absorb losses or right to receive benefits that could be potentially significant to the VIE. The Company continually reassesses whether it is the primary beneficiary of a VIE throughout the entire period the Company is involved with the VIE. The Company also determines whether decision-maker or service-provider fees are variable interests. Decision-maker or service-provider fees are not considered variable interests when the arrangement does not expose the Company to risks of loss that a potential VIE was designed to pass on to its variable interest holders, the fees are commensurate, the arrangement is at market, and the Company does not have any other interests (including direct interests and certain indirect interests held through related parties) that absorb more than an insignificant amount of a VIE’s potential variability. This determination can have a significant impact on the Company’s consolidation analysis, as it could affect whether a legal entity is a VIE and whether the Company is the primary beneficiary of a VIE. When the Company’s decision-maker or service-provider fee is not a variable interest, the Company is viewed as acting as a fiduciary for the potential VIE. The following tables present a summary of financial assets and liabilities from the Company’s involvement with consolidated VIEs: Assets Liabilities Net Assets December 31, 2022 Consolidated securitization $ — $ — $ — Consolidated warehouse entities 488,337 337,269 151,068 Other consolidated VIEs 496,144 561 495,583 Total consolidated VIEs $ 984,481 $ 337,830 $ 646,651 Assets Liabilities Net Assets September 30, 2023 Consolidated securitization $ 205,107 $ 153,782 $ 51,325 Consolidated warehouse entities 551,045 352,435 198,610 Other consolidated VIEs 244,633 1,837 242,796 Total consolidated VIEs $ 1,000,785 $ 508,054 $ 492,731 Consolidated Securitization On July 6, 2023, the Company completed a private securitization securities offering (“UPST 2023-2”). As a retaining sponsor of the transaction, under risk retention requirements in Title 17 U.S. Code of Federal Regulations Part 246, Credit Risk Retention, promulgated by the Securities and Exchange Commission, the Company is required to retain at least 5% of the economic risk in UPST 2023-2. The Company elected to satisfy the risk retention requirements by holding eligible vertical retained interests in the form of a combination of securitization notes and residual certificates. The Company has also retained the remainder of the residual certificates issued as part of the transaction. The Company was the sole contributor of the collateral, which included $204.7 million unpaid principal balance of Upstart-powered loans held by the Company. The weighted-average coupon of the securitization notes issued was approximately 9.2%, and their sale generated approximately $165.3 million in gross cash proceeds. These proceeds and payments made on securitization notes are classified as financing activities in the statement of cash flows. Upon closing of UPST 2023-2, the Company determined that servicing fees represent a variable interest due to the retained interests held by the Company. The retained interests held by the Company were deemed to potentially absorb more than an insignificant amount of expected losses or expected returns at the inception of the securitization transaction. The Company, as servicer, also has the power to direct the activities that most significantly impact the economics of the entities associated with the UPST 2023-2 securitization, and as such, the Company determined it was the primary beneficiary and consolidated the entities associated with UPST 2023-2. The loans held in the consolidated securitization trust are classified as held-for-sale and included in loans, at fair value, and the notes sold to third-party investors are recorded at fair value as payable to securitization note holders on the condensed consolidated balance sheets. Refer to “ Note 6. Fair Value Measurement ” for additional information on determination of fair value of these assets and liabilities. The value of the residual certificates issued as part of the securitization and retained by the Company was eliminated as part of the consolidation. Warehouse Entities The Company established Upstart Loan Trust (“ULT”) and Upstart Auto Warehouse Trust (“UAWT”) to enter into warehouse credit facilities for the purpose of purchasing Upstart-powered loans. Refer to “ Note 9. Borrowings ” for additional information. The entities are Delaware statutory trusts that are structured to be bankruptcy-remote, with third-party banks operating as trustees. Other Consolidated VIE The Company has formed a number of VIEs for the purpose of holding Upstart-powered loans that are not pledged or eligible to be pledged to the Company’s warehouse credit facilities. Unconsolidated VIEs The Company’s transactions with unconsolidated VIEs include securitizations of unsecured personal whole loans and sales of whole loans to VIEs. While the Company continues to be involved with the unconsolidated VIEs in its role as the sponsor and the servicer of securitization transactions, the Company does not hold a significant economic interest in these entities and has determined that it is not the primary beneficiary of these entities. The Company’s unconsolidated VIEs include entities established as the issuers and grantor trusts for various securitization transactions. In cases where the VIEs are not consolidated and the transfer of the loans from the Company to the securitization trust meets sale accounting criteria, the Company recognizes a gain or loss on sales of loans. The net proceeds of the sale represent the fair value of any assets obtained or liabilities incurred as part of the transaction. The assets are transferred into a trust such that the assets are legally isolated from the creditors of the Company and are not available to satisfy obligations of the Company. These assets can only be used to settle obligations of the underlying securitization trusts. During the three months ended September 30, 2023, the Company exercised a clean up call related to two unconsolidated VIEs and subsequently liquidated the associated entities. A clean up call option allows the Company, as servicer, to repurchase the remaining transferred financial asset once the collateral falls below a predefined level, which represents the point where servicing becomes administratively burdensome. The clean up calls had no material impact on the condensed consolidated financial statements of the Company. The following tables summarize the aggregate value of assets and liabilities of unconsolidated VIEs in which the Company holds a variable interest but is not the primary beneficiary: Assets Liabilities Net Assets Maximum Exposure to Losses December 31, 2022 Securitizations and other $ 364,013 $ 265,040 $ 98,973 $ 13,311 Assets Liabilities Net Assets Maximum Exposure to Losses September 30, 2023 Securitizations and other $ 222,125 $ 158,018 $ 64,107 $ 8,758 The Company’s maximum exposure to loss from its involvement with unconsolidated VIEs represents the estimated loss that would be incurred under severe, hypothetical circumstances, for which the Company believes the possibility is remote. The carrying value of assets that relate to variable interests in unconsolidated VIEs consists of $6.2 million and $2.8 million of securitization notes and residual certificates which are included in other assets on the condensed consolidated balance sheets as of December 31, 2022 and September 30, 2023, respectively. The Company also had $7.1 million and $6.0 million of cash deposits held as reserve accounts for related securitizations, included in other assets on the condensed consolidated balance sheets as of December 31, 2022 and September 30, 2023. For securitization transactions where the Company is not the risk retaining sponsor, and servicing is the only form of continuing involvement, the Company would only experience a loss if it were required to repurchase such a loan due to a breach in representations and warranties and is not able to collect all repayments, refer to “ Note 12. Commitments and Contingencies ” for further information. The investors and the securitization trusts have no direct recourse to the Company’s assets, and holders of the securities issued by the securitization trusts can look only to the assets of the securitization trusts that issued their

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments In February 2023 and June 2023, UAWT and ULT entered into interest rate cap agreements with a strike rate of 3.0% and 3.25%, respectively. The agreements were entered into in relation to the warehouse credit facilities which bear floating interest rates, refer to “Note 9. Borrowings” for further information. The interest rate caps provide protection to the credit facilities against exposure to changes in cash flows to the extent the underlying interest rate on the facility exceeds the strike rate. The UAWT interest rate cap matures in April 2029 and the ULT interest rate cap matures June 2025. The interest rate cap agreements meet the definition of a derivative and are reported at fair value. Refer to “ Note 6. Fair Value Measurement ” for additional information. The following table presents the notional amount as well as the fair value of interest rate caps, which is reported as part of other assets on the condensed consolidated balance sheets. There were no material derivative financial instruments held by the Company as of December 31, 2022. September 30, 2023 Notional Amount Fair Value Interest rate caps $ 315,992 $ 9,796 The Company recognizes changes in fair value of these instruments in earnings and reports them as part of the interest expense on the condensed consolidated statements of operations and comprehensive loss. The table below presents gains recognized on the interest rate caps during the following periods: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Fair value gains, net on interest rate caps $ — $ 1,504 $ — $ 2,549

Beneficial Interests

Beneficial Interests	9 Months Ended
	Sep. 30, 2023
Beneficial Interests [Abstract]
Beneficial Interests	Beneficial Interests In connection with certain committed capital agreements, the Company has risk sharing arrangements in which it is obligated to make payments to the loan buyer or is entitled to receive payments from the loan buyer if credit losses on the underlying loans subject to the arrangements deviate from initial expectations, subject to a dollar cap. The Company has beneficial interests in these arrangements which either meet the definition of a derivative or that meet the criteria of a debt security. As of September 30, 2023 the Company’s capital at risk, which represents the maximum exposure to losses, under these arrangements was $66.1 million. The following table presents the aggregate unpaid principal balance of the underlying portfolio as well as the fair value of beneficial interests, which are presented as a separate asset line item on the condensed consolidated balance sheets. As of September 30, 2023, beneficial interest liabilities were immaterial and their value is included in other liabilities on the condensed consolidated balance sheets. There were no beneficial interests assets or liabilities held by the Company as of December 31, 2022. September 30, 2023 Unpaid Principal Balance Fair Value Beneficial interests $ 1,227,371 $ 36,974 The Company recognizes these beneficial interests at fair value with changes reported as part of the fair value and other adjustments on the condensed consolidated statements of operations and comprehensive loss . The table below presents losses recognized on beneficial interests during the following periods: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Fair value losses on beneficial interests $ — $ (7,171) $ — $ (9,127) Refer to “ Note 6. Fair Value Measurement ” for additional information.

Fair Value Measurement

Fair Value Measurement	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurement The following table presents assets and liabilities measured at fair value and categorized in accordance with the fair value hierarchy: December 31, September 30, Level 2022 2023 Assets Loans 3 $ 1,010,421 $ 972,336 Notes receivable and residual certificates 3 6,181 2,786 Loan servicing assets 3 36,467 30,091 Interest rate caps (1) 2 — 9,796 Beneficial interests 3 — 36,974 Total assets $ 1,053,069 $ 1,051,983 Liabilities Loan servicing liabilities 3 $ 3,968 $ 2,393 Payable to securitization note holders 3 — 153,782 Trailing fee liabilities 3 4,852 4,173 Total liabilities $ 8,820 $ 160,348 (1) The fair value of interest rate caps is determined based on the present value of the estimated future cash flows over the contract term using observable market-based inputs as of the valuation date, including implied interest rates. Financial instruments are categorized in the fair value hierarchy based on the significance of unobservable inputs and assumptions in the overall fair value measurement. Since the Company’s loans, notes receivable and residual certificates, loan servicing assets and liabilities, beneficial interests, payables to securitization note holders, and trailing fee liabilities do not trade in an active market with readily observable prices, the Company uses significant unobservable inputs to measure the fair value of these assets and liabilities. There were no transfers between Level 1, Level 2 or Level 3 of the fair value hierarchy during the periods presented. Loans Loans included in the Company’s condensed consolidated balance sheets are classified as either held-for-sale or held-for-investment based on the Company’s intent and ability to sell the loans prior to maturity. Loans held-for-sale in consolidated securitization include loans contributed as collateral to and held in the consolidated securitization (UPST 2023-2). From time to time the Company transfers loans between classifications based on changes in the Company’s intent and ability. The following table presents the fair value of classes of loans included in the Company’s consolidated balance sheets as of December 31, 2022 and September 30, 2023: December 31, September 30, 2022 2023 Loans held-for-sale $ 882,810 $ 632,316 Loans held-for-investment 127,611 143,493 Loans held in consolidated securitization — 196,527 Total $ 1,010,421 $ 972,336 Valuation Methodology Loans held-for-sale and held-for-investment are measured at estimated fair value using a discounted cash flow model. The fair valuation methodology considers projected prepayments and historical defaults, losses and recoveries to project future losses and net cash flows on loans. Net cash flows are discounted using an estimate of market rates of return. The fair value of these loans also includes accrued interest. As described in Note 1. Description of Business and Significant Accounting Policies , the Company elected the measurement alternative under Topic 810, Consolidation, and maximizes the use of observable inputs to estimate the fair value of the financial assets and liabilities of UPST 2023-2. Under the measurement alternative, the Company determined that inputs used to determine the value of UPST 2023-2 liabilities, which consist of securitization notes and residual certificates issued as part of this securitization, are more observable than those used to measure fair value of UPST 2023-2 financial assets, which consist of held-for-sale loans contributed as collateral. Thus, the loans are measured based on the sum of the fair value of the UPST 2023-2 securitization notes and residual certificates, with changes in fair value included in the consolidated statements of operations and comprehensive loss. Significant Inputs and Assumptions The following table presents quantitative information about the significant unobservable inputs used for the Company’s Level 3 fair value measurements for loans held-for-sale and held-for-investment: December 31, 2022 September 30, 2023 Minimum Maximum Weighted-Average (2) Minimum Maximum Weighted-Average (2) Discount rate 6.36 % 22.28 % 11.87 % 10.22 % 23.06 % 12.17 % Credit risk rate (1) 0.01 % 93.09 % 16.93 % 0.01 % 92.90 % 16.97 % Prepayment rate (1) 0.08 % 93.43 % 40.49 % 0.13 % 93.43 % 37.85 % (1) Expressed as a percentage of the original principal balance of the loans (2) Unobservable inputs were weighted by relative fair value The following table presents quantitative information about the significant unobservable inputs used for the Company’s Level 3 fair value measurements for loans held in consolidated securitization: December 31, 2022 September 30, 2023 Minimum Maximum Weighted-Average (2) Minimum Maximum Weighted-Average (2) Discount rate * * * 10.64 % 23.05 % 12.93 % Credit risk rate (1) * * * 0.61 % 37.70 % 15.56 % Prepayment rate (1) * * * 6.66 % 89.84 % 43.03 % (1) Expressed as a percentage of the original principal balance of the loans (2) Unobservable inputs were weighted by relative fair value Discount rates –The discount rates are rates of return used to discount future expected cash flows to arrive at a present value, which represents the fair value. The discount rates used for the projected net cash flows are the Company’s estimates of the rates of return that market participants would require when investing in these financial instruments with cash flows dependent on credit quality of the related loan. A risk premium component is implicitly included in the discount rates to reflect the amount of compensation market participants require due to the uncertainty inherent in the instruments’ cash flows resulting from risks such as credit and liquidity. Credit risk rates –The credit risk rates are an estimate of the net cumulative principal payments that will not be repaid over the entire life of a financial instrument. The credit risk rates are expressed as a percentage of the original principal amount of the instrument. The estimated net cumulative loss represents the sum of the net losses estimated to occur each month of the life of the instrument, net of the average recovery expected to be received. Prepayment rates –Prepayment rates are an estimate of the cumulative principal prepayments that will occur over the entire life of a loan as a percentage of the original principal amount of the loan. The assumption regarding cumulative prepayments impacts the projected balances and expected terms of the loans. The above inputs are similarly used in estimating fair value of related financial instruments. Refer to the Assets and Liabilities related to Securitization Transactions section below for additional information. Significant Recurring Level 3 Fair Value Input Sensitivity The following table presents the sensitivity of the fair value of loans held-for-sale and held-for-investment to adverse changes in key assumptions used in the valuation model as of December 31, 2022 and September 30, 2023, respectively. December 31, September 30, 2022 2023 Fair value of loans held-for-sale and held-for-investment $ 1,010,421 $ 775,809 Discount rates 100 basis point increase (11,979) (9,167) 200 basis point increase (23,720) (18,153) Expected credit loss rates on underlying loans 10% adverse change (11,927) (9,739) 20% adverse change (23,852) (19,513) Expected prepayment rates 10% adverse change (2,284) (1,904) 20% adverse change (4,530) (3,763) The following table presents the sensitivity of the fair value of loans in consolidated securitization to adverse changes in key assumptions used in the valuation model as September 30, 2023. No loans were held in consolidated securitization as of December 31, 2022. December 31, September 30, 2022 2023 Fair value of loans held in consolidated securitization $ — $ 196,527 Discount rates 100 basis point increase — (2,660) 200 basis point increase — (5,264) Expected credit loss rates on underlying loans 10% adverse change — (2,758) 20% adverse change — (5,449) Expected prepayment rates 10% adverse change — (2,090) 20% adverse change — (4,142) Rollforward of Level 3 Fair Values The following tables include a rollforward of the loans classified within Level 3 of the fair value hierarchy: Loans Held-for- Loans Held-for-Investment Loans Held in Consolidated Securitization Total Fair value at June 30, 2022 $ 605,319 $ 18,444 $ — $ 623,763 Purchases of loans 333,779 41,402 — 375,181 Sale of loans (232,302) — — (232,302) Purchase of loans for immediate resale 722,080 — — 722,080 Immediate resale of loans (722,080) — — (722,080) Repayments received (43,748) (2,699) — (46,447) Changes in fair value recorded in earnings (16,499) (4,560) — (21,059) Other changes 629 690 — 1,319 Fair value at September 30, 2022 $ 647,178 $ 53,277 $ — $ 700,455 Loans Held-for- Loans Held-for-Investment Loans Held in Consolidated Securitization Total Fair value at December 31, 2021 $ 142,685 $ 109,792 $ — $ 252,477 Reclassification of loans from HFS to HFI 103,679 (103,679) — — Purchases of loans 1,459,544 55,278 — 1,514,822 Sale of loans (866,984) — — (866,984) Purchase of loans for immediate resale 5,519,116 — — 5,519,116 Immediate resale (5,519,116) — — (5,519,116) Repayments received (128,023) (3,737) — (131,760) Changes in fair value recorded in earnings (68,329) (5,047) — (73,376) Other changes 4,606 670 — 5,276 Fair value at September 30, 2022 $ 647,178 $ 53,277 $ — $ 700,455 Loans Held-for- Loans Held-for-Investment Loans Held in Consolidated Securitization Total Fair value at June 30, 2023 $ 689,851 $ 147,714 $ — $ 837,565 Transfer of loans to consolidated securitization (1) (209,968) — 209,968 — Purchases of loans (2) 483,921 32,714 — 516,635 Sale of loans (269,627) — — (269,627) Purchase of loans for immediate resale 342,467 — — 342,467 Immediate resale of loans (342,467) — — (342,467) Repayments received (40,894) (24,757) (12,302) (77,953) Changes in fair value recorded in earnings (20,203) (13,235) (1,139) (34,577) Other changes (764) 1,057 — 293 Fair value at September 30, 2023 $ 632,316 $ 143,493 $ 196,527 $ 972,336 (1) Transfer of loans to consolidated securitization at fair value. (2) Purchase activity includes an immaterial unpaid principal balance related to securitization clean-up calls during the three months ended September 30, 2023. Loans Held-for- Loans Held-for-Investment Loans Held in Consolidated Securitization Total Fair value at December 31, 2022 $ 882,810 $ 127,611 $ — $ 1,010,421 Transfer of loans to consolidated securitization (1) (209,968) — 209,968 — Purchases of loans (2) 1,053,309 121,293 — 1,174,602 Sale of loans (888,019) — — (888,019) Purchase of loans for immediate resale 1,023,426 — — 1,023,426 Immediate resale of loans (1,023,426) — — (1,023,426) Repayments received (149,697) (68,212) (12,302) (230,211) Changes in fair value recorded in earnings (54,767) (40,003) (1,139) (95,909) Other changes (1,352) 2,804 — 1,452 Fair value at September 30, 2023 $ 632,316 $ 143,493 $ 196,527 $ 972,336 (1) Transfer of loans to consolidated securitization at fair value. (2) Purchase activity includes an immaterial unpaid principal balance related to securitization clean-up calls during the nine months ended September 30, 2023. The following table presents the aggregate fair value and aggregate principal outstanding of all loans and loans that were 90 days or more past due included in the condensed consolidated balance sheets: Loans Loans > 90 Days Past Due December 31, September 30, December 31, September 30, 2022 2023 2022 2023 Outstanding principal balance $ 1,047,714 $ 1,002,387 $ 9,006 $ 12,811 Net fair value and accrued interest adjustments (37,293) (30,051) (7,006) (10,528) Fair value (1) $ 1,010,421 $ 972,336 $ 2,000 $ 2,283 (1) Includes $397.7 million and $379.5 million of auto loans as of December 31, 2022 and September 30, 2023, respectively, of which an immaterial amount is 90 days or more past due for each period presented. The Company places loans on non-accrual status at 120 days past due. Any accrued interest recorded in relation to these loans is reversed in the respective period. The Company charges-off loans no later than 120 days past due. Assets and Liabilities related to Securitization Transactions As of December 31, 2022 and September 30, 2023, the Company held notes receivable and residual certificates with an aggregate fair value of $6.2 million and $2.8 million, respectively, within other assets on the Company’s condensed consolidated balance sheets. The balances consist of securitization notes and residual certificates retained from unconsolidated securitization transactions. As of September 30, 2023, the Company recognized payables to securitization note holders of $153.8 million at fair value. The balance represents the value of the securitization notes issued and owned by third-party investors in connection with UPST 2023-2. Accrued interest on these financial instruments is immaterial as of September 30, 2023. The value of the UPST 2023-2 securitization notes and residual certificates retained by the Company is eliminated in the consolidation process. As of December 31, 2022, the Company did not hold liabilities related to the consolidated securitization transaction. Valuation Methodology The discounted cash flow methodology, which is used to estimate the fair value of notes and residual certificates issued as part of the Company’s securitizations, uses the same projected net cash flows as their collateral loan pools. This model uses inputs that are inherently judgmental and reflect the Company’s best estimates of the assumptions a market participant would use to calculate fair value. Significant Inputs and Assumptions The following table presents quantitative information about the significant unobservable inputs used for the Company’s Level 3 fair value measurements of the underlying collateral pools of the assets and liabilities related to securitization transactions: December 31, 2022 September 30, 2023 Minimum Maximum Weighted-Average (2) Minimum Maximum Weighted-Average (2) Notes receivable and residual certificates Discount rate 8.42 % 22.27 % 12.79 % 10.64 % 23.05 % 13.42 % Credit risk rate (1) 0.59 % 50.69 % 18.43 % 0.59 % 50.69 % 17.78 % Prepayment rate (1) 10.90 % 88.73 % 42.66 % 10.90 % 87.53 % 44.13 % Payable to securitization note holders Discount rate * * * 10.64 % 23.05 % 12.93 % Credit risk rate (1) * * * 0.61 % 37.70 % 15.56 % Prepayment rate (1) * * * 6.66 % 89.84 % 43.03 % (1) Expressed as a percentage of the original principal balance of the loans underlying the financial instruments (2) Unobservable inputs were weighted by relative fair value * Not applicable Significant Recurring Level 3 Fair Value Input Sensitivity Notes Receivable and Residual Certificates Adverse changes in discount rates, credit risk rates, or prepayment rates do not result in a material impact to the fair value of notes receivable and residual certificates as of December 31, 2022 and September 30, 2023. Payable to Securitization Note Holders The fair value of the payable to securitization note holders is sensitive to adverse changes in discount rates, which represent estimates of the rates of return that institutional investors would require when investing in financial instruments with similar risk and return characteristics. On average, a hypothetical 100 and 200 basis point increase in discount rates results in a decrease in fair value of payable to securitization note holders of $2.2 million and $4.3 million, respectively, as of September 30, 2023. Adverse changes in credit risk rates and expected prepayment rates do not result in a material impact to the fair value of payable to securitization note holders as of September 30, 2023. The Company held no payable to securitization note holders as of December 31, 2022. Rollforward of Level 3 Fair Values The following tables include a rollforward of the notes receivable and residual certificates and payables to securitization note holders related to securitization transactions classified by the Company within Level 3 of the fair value hierarchy: Notes Receivable and Residual Certificates Payable to Securitization Note Holders Fair value at June 30, 2022 $ 4,698 $ — Repayments and settlements (1,596) — Changes in fair value recorded in earnings 357 — Fair value at September 30, 2022 $ 3,459 $ — Notes Receivable and Residual Certificates Payable to Fair value at December 31, 2021 $ 8,288 $ — Repayments and settlements (5,508) — Changes in fair value recorded in earnings 679 — Fair value at September 30, 2022 $ 3,459 $ — Notes Receivable and Residual Certificates Payable to Fair value at June 30, 2023 $ 3,907 $ — Additions — 165,318 Repayments and settlements (560) (10,016) Changes in fair value recorded in earnings (561) (1,520) Fair value at September 30, 2023 $ 2,786 $ 153,782 Notes Receivable and Residual Certificates Payable to Fair value at December 31, 2022 $ 6,181 $ — Additions — 165,318 Repayments and settlements (3,556) (10,016) Changes in fair value recorded in earnings 161 (1,520) Fair value at September 30, 2023 $ 2,786 $ 153,782 Loan Servicing Assets and Liabilities Valuation Methodology Loan servicing assets and liabilities are measured at estimated fair value using a discounted cash flow model. The cash flows in the valuation model represent the difference between the contractual servicing fees charged to institutional investors and an estimated market servicing fee. Since contractual servicing fees are generally based on the monthly unpaid principal balance of the underlying loans, the expected cash flows in the model incorporate estimates of net losses and prepayments. Significant Inputs and Assumptions The following table presents quantitative information about the significant unobservable inputs used for the Company’s Level 3 fair value measurements for loan servicing assets and liabilities: December 31, 2022 September 30, 2023 Minimum Maximum Weighted-Average (2) Minimum Maximum Weighted-Average (2) Discount rate 13.00 % 20.00 % 17.20 % 13.00 % 20.00 % 16.92 % Credit risk rate (1) 0.03 % 91.76 % 16.22 % 0.05 % 81.10 % 15.04 % Market-servicing rate (3)(4)(5) 0.62 % 3.72 % 0.62 % 0.62 % 3.72 % 0.63 % Prepayment rate (1) 0.53 % 91.99 % 41.19 % 2.17 % 96.90 % 41.57 % (1) Expressed as a percentage of the original principal balance of the loans underlying the servicing arrangement (2) Unobservable inputs were weighted by relative fair value (3) Excludes ancillary fees that would be passed on to a third-party servicer (4) Expressed as a percentage of the outstanding principal balance of the loan (5) Includes personal loans and auto loans Discount rates –The discount rates are the Company’s estimate of the rates of return that market participants would require when investing in similar servicing rights. Discount rates for servicing rights on existing loans are adjusted to reflect the time value of money and a risk premium intended to reflect the amount of compensation market participants would require due to the uncertainty associated with these instruments’ cash flows. Credit risk rate s–The credit risk rates are the Company’s estimate of the net cumulative principal payments that will not be repaid over the entire life of a loan expressed as a percentage of the original principal amount of the loan. The assumption regarding net cumulative losses impacts the projected balances and expected terms of the loans, which are used to project future servicing revenues. Market-servicing rates –Market-servicing rate is an estimated measure of adequate compensation for a market participant, if one was required. The rate is expressed as a fixed percentage of outstanding principal balance per annum. The estimate considers the profit that would be demanded in the marketplace to service the portfolio of outstanding loans subject to the Company’s servicing agreements. Prepayment rates –Prepayment rates are the Company’s estimate of the cumulative principal prepayments that will occur over the entire life of a loan as a percentage of the original principal amount of the loan. The assumption regarding cumulative prepayments impacts the projected balances and expected terms of the loans, which are used to project future servicing revenues. Significant Recurring Level 3 Fair Value Input Sensitivity The table below presents the fair value sensitivity of loan servicing assets and liabilities to adverse changes in key assumptions. The fair value of loan servicing assets and liabilities is not sensitive to adverse changes in discount rates and prepayment rates as such changes would not result in a significant impact on the fair value as of December 31, 2022 and September 30, 2023, respectively. December 31, September 30, 2022 2023 Fair value of loan servicing assets $ 36,467 $ 30,091 Expected market-servicing rates 10% market-servicing rates increase (9,989) (5,689) 20% market-servicing rates increase (19,950) (16,101) December 31, September 30, 2022 2023 Fair value of loan servicing liabilities $ 3,968 $ 2,393 Expected market-servicing rates 10% market-servicing rates increase 2,303 1,329 20% market-servicing rates increase 4,640 2,702 Rollforward of Level 3 Fair Values The following tables present a rollforward of the loan servicing assets and liabilities classified by the Company within Level 3 of the fair value hierarchy: Loan Servicing Assets Loan Servicing Liabilities Fair value at June 30, 2022 $ 35,171 $ 6,366 Sale of loans 6,048 9 Changes in fair value recorded in earnings (4,182) (1,565) Fair value at September 30, 2022 $ 37,037 $ 4,810 Loan Servicing Assets Loan Servicing Liabilities Fair value at December 31, 2021 $ 18,388 $ 8,780 Sale of loans 26,066 2,296 Changes in fair value recorded in earnings (7,417) (6,266) Fair value at September 30, 2022 $ 37,037 $ 4,810 Loan Servicing Assets Loan Servicing Liabilities Fair value at June 30, 2023 $ 33,339 $ 2,577 Sale of loans 3,475 3 Changes in fair value recorded in earnings (6,723) (187) Fair value at September 30, 2023 $ 30,091 $ 2,393 Loan Servicing Assets Loan Servicing Liabilities Fair value at December 31, 2022 $ 36,467 $ 3,968 Sale of loans 10,512 80 Changes in fair value recorded in earnings (16,888) (1,655) Fair value at September 30, 2023 $ 30,091 $ 2,393 Beneficial Interests In connection with certain loan sale agreements, the Company is obligated to make payments to the loan buyer or is entitled to receive payments from the buyer if credit losses on personal loans subject to the arrangement deviate from initial expectations, subject to a dollar cap. These arrangements are recorded on the condensed consolidated balance sheet as beneficial interests. As of September 30, 2023, the Company held beneficial interests assets related to these arrangements of $37.0 million. The Company held no beneficial interests as of December 31, 2022. Valuation Methodology Beneficial interests are measured at estimated fair value using a discounted cash flow model. The fair valuation methodology considers projected defaults, losses and recoveries to project future losses and net cash flows on the underlying loans. Net cash flows are discounted using an estimate of market rates of return that reflect the risk premium related to those cash flows. The models use inputs that are inherently judgmental and reflect the Company’s best estimates of the assumptions a market participant would use to determine fair value. Significant Inputs and Assumptions The following table presents quantitative information about the significant unobservable inputs used for the Company’s fair value measurements of beneficial interests as of September 30, 2023: Minimum Maximum Weighted-Average (1) Beneficial interests Discount rate 7.00 % 14.00 % 13.81 % Credit risk rate spread (2) (5.70) % 0.00 % (5.70) % (1) Unobservable inputs were weighted by relative fair value. (2) Expressed as a percentage of cumulative loss expectations as of the valuation date compared to the origination date. Discount rates –The discount rates are rates of return used to discount future expected cash flows to arrive at a present value, which represents the fair value. The discount rates used for the projected net cash flows are the Company’s estimates of the rates of return that market participants would require when investing in these financial instruments with cash flows dependent on credit performance of the underlying loan portfolio. A risk premium component is implicitly included in the discount rates to reflect the amount of compensation market participants require due to the uncertainty inherent in the instruments’ cash flows resulting from risks such as credit and liquidity. The Company uses two different discount rates for expected cash flows associated with demonstrated to-date credit performance and those associated with future credit performance. The difference in these rates reflects the level of uncertainty and, as a result, risk premium that would be required by market participants when investing in these instruments. Credit risk rate spreads –Credit risk rates for beneficial interests are determined the same way as for underlying loan portfolios. Credit risk rates are an estimate of cumulative losses, net of average recoveries, of the underlying portfolio, which represent the amount of principal that will not be repaid over the entire life of a financial instrument. The credit risk rate spreads are the relative difference, expressed as a percentage, between the expected credit risk rate on origination date and the estimated credit risk rate as of a valuation date. The following table presents the sensitivity of beneficial interests to adverse changes in key assumptions used in the valuation model as of September 30, 2023. September 30, 2023 Fair value of beneficial interests $ 36,974 Discount rate 100 basis point increase (879) 200 basis point increase (1,725) Expected credit rate spreads on underlying loans 10% adverse change (10,044) 20% adverse change (15,789) The following tables present a rollforward of beneficial interests: Beneficial Interests Fair value as of June 30, 2023 $ 28,664 Additions 14,719 Changes in fair value recorded in earnings (6,409) Fair value as of September 30, 2023 $ 36,974 Beneficial Interests Fair value as of December 31, 2022 $ — Additions 45,254 Changes in fair value recorded in earnings (8,280) Fair value as of September 30, 2023 $ 36,974 Trailing Fee Liabilities The Company pays certain bank partners monthly trailing fees based on the amount and timing of principal and interest payments made by borrowers of the underlying loans. Significant inputs used for estimating the fair value of trailing fee liabilities included discount rates of 6.36% to 22.28% and credit risk rates of 0.01% to 93.09% as of December 31, 2022 and discount rates of 10.22% to 23.06% and credit risk rates of 0.01% to 92.90% as of September 30, 2023. The fair value sensitivity of trailing fee liabilities to adverse changes in key assumptions would not result in a material impact on the Company’s financial position or the results of operations. Rollforward of Level 3 Fair Values The following tables include a rollforward of trailing fee liabilities classified by the Company within Level 3 of the fair value hierarchy: Trailing Fee Liabilities Fair value at June 30, 2022 $ 5,446 Issuances 618 Repayments and settlements (816) Changes in fair value recorded in earnings (47) Fair value at September 30, 2022 $ 5,201 Trailing Fee Liabilities Fair value at December 31, 2021 $ 4,315 Issuances 3,404 Repayments and settlements (2,211) Changes in fair value recorded in earnings (307) Fair value at September 30, 2022 $ 5,201 Trailing Fee Liabilities Fair value at June 30, 2023 $ 4,265 Issuances 580 Repayments and settlements (670) Changes in fair value recorded in earnings (2) Fair value at September 30, 2023 $ 4,173 Trailing Fee Liabilities Fair value at December 31, 2022 $ 4,852 Issuances 1,414 Repayments and settlements (2,096) Changes in fair value recorded in earnings 3 Fair value at September 30, 2023 $ 4,173

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
	Sep. 30, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible assets	Goodwill and Intangible Assets Goodwill During the nine months ended September 30, 2023, there were no changes in the carrying amount of goodwill of $67.1 million on the Company’s condensed consolidated balance sheets. Intangible Assets Acquired intangible assets subject to amortization consist of developed technology and customer relationships, and are recorded net of amortization and included within other assets on the condensed consolidated balance sheets. The gross and net carrying values and accumulated amortization are as follows: Developed Technology December 31, 2022 September 30, Gross carrying amount $ 9,400 $ 9,400 Accumulated amortization (5,483) (7,833) Net carrying value $ 3,917 $ 1,567 Customer Relationships December 31, 2022 September 30, Gross carrying amount $ 13,700 $ 13,700 Accumulated amortization (1,998) (2,854) Net carrying value $ 11,702 $ 10,846 Amortization expense was $1.1 million for both the three months ended September 30, 2022 and 2023 and was $3.2 million for both the nine months ended September 30, 2022 and 2023. Expected future amortization expense for intangible assets as of September 30, 2023 is as follows: Fiscal Years: Remaining 2023 $ 1,069 2024 1,925 2025 1,142 2026 1,142 2027 1,142 Thereafter 5,993 Total $ 12,413

Balance Sheet Components

Balance Sheet Components	9 Months Ended
	Sep. 30, 2023
Other Assets [Abstract]
Balance Sheet Components	Balance Sheet Components Other Assets Other assets consisted of the following: December 31, September 30, 2022 2023 Servicing fees and other receivables $ 46,652 $ 41,191 Loan servicing assets (at fair value) 36,467 30,091 Prepaid expenses 16,740 21,052 Intangible assets, net (1) 15,631 12,425 Interest rate caps (2) — 9,796 Deposits 10,002 8,666 Notes receivable and residual certificates (at fair value) 6,181 2,786 Other assets 22,678 17,773 Total other assets $ 154,351 $ 143,780 (1) Refer to “ Note 7. Goodwill and Intangible Assets ” for further information. (2) Refer to “ Note 4. Derivative Financial Instruments” for further information. Servicing fees and other receivables represent amounts recognized as revenue but not yet collected in relation to servicing and other agreements with institutional investors and lending partners. Property, Equipment, and Software, Net Property, equipment, and software, net consisted of the following: December 31, September 30, 2022 2023 Internally developed software $ 37,783 $ 52,808 Leasehold improvements 13,074 14,050 Computer and networking equipment 6,049 6,054 Furniture and fixtures 4,421 4,736 Total property, equipment, and software 61,327 77,648 Accumulated depreciation and amortization (17,159) (29,638) Total property, equipment, and software, net $ 44,168 $ 48,010 Depreciation and amortization expense on property, equipment, and software was $2.7 million and $6.7 million for the three and nine months ended September 30, 2022, respectively, and was $3.9 million and $12.6 million for the three and nine months ended September 30, 2023, respectively. Capitalized internally developed software balances, net of accumulated amortization, were $27.4 million and $32.4 million as of December 31, 2022 and September 30, 2023, respectively. The Company also recognized impairment charges to internally developed software of $2.6 million during the nine months ended September 30, 2023, as a result of the January 2023 Plan. There were no impairment charges during the three months ended September 30, 2023. Refer to “ Note 15. Reorganization Expenses ” for more information. Accrued Expenses and Other Liabilities Accrued expenses and other liabilities consisted of the following: December 31, September 30, 2022 2023 Accrued expenses $ 23,506 $ 19,689 Accrued payroll 21,825 21,303 Loan servicing liabilities (at fair value) 3,968 2,393 Trailing fee liability (at fair value) 4,852 4,173 Other liabilities 12,795 4,295 Total accrued expenses and other liabilities $ 66,946 $ 51,853

Borrowings

Borrowings	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Borrowings	Borrowings The following table presents the aggregate principal outstanding of all debt mentioned in this note that are included in the condensed consolidated balance sheets: Borrowings December 31, September 30, 2022 2023 Warehouse credit facilities $ 336,452 $ 351,154 Convertible senior notes 661,250 661,250 Total payments due 997,702 1,012,404 Unamortized debt discount (11,308) (9,012) Total borrowings $ 986,394 $ 1,003,392 Warehouse Credit Facilities Upstart Loan Trust Warehouse Credit Facility In November 2015, the Company’s consolidated VIE, ULT, entered into a revolving credit and security agreement with a third-party lender (the “ULT Warehouse Credit Facility”). The credit and security agreement for the ULT Warehouse Credit Facility was amended and restated in its entirety in May 2020 and has been further amended from time to time. Under the revolving credit and security agreement, as amended from time to time, ULT may borrow up to $175.0 million until the earlier of June 15, 2025 and the occurrence of an accelerated amortization event. Accelerated amortization events include, but are not limited to, failure to satisfy certain loan performance metrics or the occurrence of an event of default. The proceeds may only be used to purchase unsecured personal loans and to pay fees and expenses related to the credit facility. The ULT Warehouse Credit Facility matures on the earlier of June 15, 2026 or acceleration of the facility following an event of default, upon which date 100% of the outstanding principal amount, together with any accrued and unpaid interest, becomes due and payable. The ULT Warehouse Credit Facility bears a floating interest rate of Compounded Secured Overnight Financing Rate (“SOFR”) plus a spread ranging from 2.75% to 4.13% per annum, due and payable monthly in arrears. The Company is also subject to a monthly unused fee ranging from 0.15% to 1.00% per annum on the undrawn balance. The maximum advance rate under the ULT Warehouse Credit Facility on outstanding principal of loans held by ULT was 72.5% as of December 31, 2022 and September 30, 2023. In June 2023, ULT entered into an interest rate cap agreement intended to protect against exposure to changes in cash flows attributable to interest rate risk on the warehouse facility. Refer to “ Note 4. Derivative Financial Instruments ” for further details related to the agreement. The ULT Warehouse Credit Facility contains certain financial covenants. As of December 31, 2022 and September 30, 2023, ULT was in compliance with all applicable covenants under the ULT Warehouse Credit Facility. The creditors of ULT have no recourse to the general credit of the Company, except for certain limited obligations of ULT to its creditors that are guaranteed by the Company. The Company does not guarantee the credit performance of the loans owned by ULT, and the loans and other assets owned by ULT are not available to settle the claims of creditors of the Company. The following table includes the aggregate balances held by ULT that were pledged as collateral for the ULT Warehouse Credit Facility and included in loans at fair value and restricted cash in the condensed consolidated balance sheets: ULT Warehouse Credit Facility December 31, 2022 September 30, Outstanding borrowings $ 163,773 $ 170,303 Aggregate outstanding principal of loans pledged as collateral 228,895 236,822 Aggregate fair value of loans purchased and held by ULT 256,024 241,049 Restricted cash pledged as collateral $ 8,547 $ 5,067 Upstart Auto Warehouse Trust Credit Facility In December 2021, the Company’s consolidated VIE, UAWT, entered into a revolving credit and security agreement with a third-party lender (the “UAWT Warehouse Credit Facility”). The credit and security agreement for the UAWT Warehouse Credit Facility was amended and restated in its entirety in August 2022 and has been further amended from time to time. On January 31, 2023, UAWT entered into the Omnibus Amendment to the Credit Agreement with the existing third-party lender which extended the last date by which UAWT may make a drawdown from its existing $200 million UAWT Warehouse Credit Facility until the earlier of June 2024 or an accelerated amortization event. An accelerated amortization event includes, but is not limited to, failure to satisfy certain loan performance metrics or the occurrence of an event of default. The proceeds may only be used to purchase secured auto loans originated using Upstart’s platform and to pay fees and expenses related to the credit facility. The UAWT Warehouse Credit Facility matures in June 2025, at which time all outstanding amounts owed must be repaid. As of September 30, 2023 the UAWT Warehouse Credit Facility bears interest per annum at a rate equivalent to the weighted-average cost of commercial paper notes issued by the lender (the “UAWT Benchmark Rate”), plus a spread ranging from 3.0% to 4.0%, and the maximum advance rate under the credit facility on outstanding principal of loans held by UAWT was 82.5% as of December 31, 2022 and 80% as of September 30, 2023. All other key terms of the Omnibus Amendment to the Credit Agreement were the same as those as of December 31, 2022. In February 2023, UAWT entered into an interest rate cap agreement intended to protect against exposure to changes in cash flows attributable to interest rate risk on the warehouse facility. Refer to “ Note 4. Derivative Financial Instruments ” for further details related to the agreement. The UAWT Warehouse Credit Facility contains certain financial covenants. As of December 31, 2022 and September 30, 2023, UAWT was in compliance with all applicable covenants under the UAWT Warehouse Credit Facility. The creditors of UAWT have no recourse to the general credit of the Company, except for certain limited obligations of UAWT to its creditors that are guaranteed by the Company. The following table includes the aggregate balances held by UAWT that were pledged as collateral for the UAWT Warehouse Credit Facility and included in loans at fair value and restricted cash in the condensed consolidated balance sheets as of December 31, 2022 and September 30, 2023. UAWT Warehouse Credit Facility December 31, 2022 September 30, 2023 Outstanding borrowings $ 172,679 $ 180,851 Aggregate outstanding principal of loans pledged as collateral 221,847 308,338 Aggregate fair value of loans purchased and held by UAWT 216,539 296,694 Restricted cash pledged as collateral $ 843 $ 360 Convertible Senior Notes On August 20, 2021, the Company issued $661.3 million aggregate principal amount of 0.25% convertible senior notes due 2026 (“Notes”) pursuant to an indenture (the “Indenture”), (including the exercise in full of the initial purchasers’ option of an additional $86.3 million aggregate principal of additional notes) in a private placement to qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended. The net proceeds from the sale of the Notes were $645.5 million after deducting debt issuance costs. The Notes represent senior unsecured obligations of the Company and bear interest at a rate of 0.25% per year, payable semiannually in arrears on February 15 and August 15 of each year beginning on February 15, 2022. The Notes mature on August 15, 2026 unless earlier converted, redeemed, or repurchased in accordance with their terms. The Notes will be convertible at an initial conversion rate of 3.5056 shares of our common stock per $1,000 principal amount of Notes, which is equivalent to an initial conversion price of $285.26 per share, subject to adjustment if certain events occur. Following certain corporate events that may occur prior to the maturity date or following our issuance of a notice of redemption, the Company will increase the conversion rate for a holder who elects to convert its Notes in connection with such corporate event or during the related redemption period in certain circumstances. Additionally, upon the occurrence of a corporate event that constitutes a “fundamental change” per the Indenture, holders of the Notes may require the Company to repurchase for cash all or a portion of their respective notes at a purchase price equal to 100% of the principal amount of the Note plus accrued and unpaid interest. Holders may convert their Notes at their option any time prior to the close of business on the business day immediately preceding May 15, 2026 only under the following circumstances: (1) during any calendar quarter commencing after December 31, 2021 (and only during such calendar quarter), if the last reported sale price of the Common Stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price on each applicable trading day; (2) during the five business-day period after any five consecutive trading-day period in which the trading price per $1,000 principal amount of Notes for each trading day of such five consecutive trading-day period was less than 98% of the product of the last reported sale price of the Common Stock and the conversion rate on each such trading day; (3) if we call any or all of the Notes for redemption, at any time prior to the close of business on the second scheduled trading day immediately preceding the redemption date; or (4) upon the occurrence of specified corporate events. On or after May 15, 2026, until the close of business on the second scheduled trading day immediately preceding the maturity date, holders of the Notes may convert all or any portion of their Notes regardless of the foregoing conditions. Upon conversion, the Company will pay or deliver, as the case may be, either cash, shares of common stock or a combination of cash and shares of common stock, at its election. The Company may not redeem the Notes prior to August 20, 2024. The Company may redeem for cash all or any portion of the Notes, at our option, on or after August 20, 2024, if the last reported sale price of our common stock has been at least 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading-day period (including the last trading day of such period) ending on, and including, the trading day immediately preceding the date on which the Company provides a notice of redemption at a redemption price equal to 100% of the principal amount of the Notes to be redeemed, plus any accrued and unpaid interest to, but excluding, the redemption date. The Company accounted for the issuance of the Notes as a single liability at par as the conversion feature does not require bifurcation as a derivative under ASC 815 and the Notes were not issued at a substantial premium. Debt issuance costs related to the Notes totaled $15.7 million and consisted of underwriting fees and third-party offering costs, which are amortized to interest expense using the effective interest method over the contractual term. The Company recorded immaterial coupon interest expense for all periods presented. The Company also recorded $0.8 million and $2.3 million for the three and nine months ended September 30, 2022, respectively, and $0.8 million and $2.3 million for the three and nine months ended September 30, 2023, respectively, of amortization of debt issuance costs within other income, net on the condensed consolidated statements of operations and comprehensive loss. The effective interest rate of the Notes is 0.7%. The estimated fair value of the Notes as of December 31, 2022 and September 30, 2023 was approximately $364.8 million and $428.0 million, respectively, which represent Level 2 valuations in the fair value hierarchy. The estimated fair value was determined based on the estimated or actual bids and offers of the Notes in an over-the-counter market. The carrying value of the Notes of December 31, 2022 and September 30, 2023 was $649.9 million and $652.2 million, respectively. Capped Call Transactions The Company used $58.5 million of the net proceeds from the Notes to enter into privately negotiated capped call instruments (“Capped Calls”) with certain financial institutions. The Capped Calls each have an initial strike price of $285.26 per share, subject to certain adjustments, which corresponds to the initial conversion price of the Notes. The Capped Calls each have an initial cap price of $400.36 per share. The Capped Calls cover, subject to anti-dilution adjustments, 2.3 million shares of common stock. The Capped Calls are expected to reduce the potential dilution to common stock upon any conversion of Notes and/or offset any cash payments the Company is required to make in excess of the principal amount of converted Notes, as the case may be, in the event the market price per share of common stock, as measured under the terms of the Capped Call, is greater than the strike price of the Capped Call, with such reduction and/or offset subject to a cap. If, however, the market price per share of the common stock, as measured under the terms of the Capped Call, exceeds the cap price of the Capped Calls, there would be dilution and/or there would not be an offset of such potential cash payments, in each case, to the extent that such market price per share of the common stock exceeds the cap price of the Capped Calls. The Capped Calls expire on August 15, 2026, subject to earlier exercise. The Capped Calls were determined to be freestanding financial instruments that meet the criteria for classification in equity; as such the Capped Calls were recorded as a reduction of additional paid-in capital within stockholders’ equity. The following table summarizes the aggregate amount of maturities of all borrowings as of September 30, 2023: September 30, Remaining 2023 $ — 2024 — 2025 180,851 2026 831,553 2027 — Thereafter — Total $ 1,012,404

Stockholders_ Equity

Stockholders’ Equity	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Stockholders’ Equity	Stockholders' Equity Common Stock Reserved for Future Issuance In December 2020, the Company's amended and restated certificate of incorporation became effective, which authorizes the issuance of 700,000,000 shares of common stock with a par value of $0.0001 per share. Shares of common stock reserved for issuance, on an as-converted basis, are as follows: December 31, September 30, 2022 2023 Options issued and outstanding 12,547,010 13,014,493 Restricted stock units outstanding 6,046,796 6,391,568 Performance-based restricted stock unit outstanding 687,500 — Shares available for future issuance under 2020 plan 5,842,057 6,471,704 Shares available for issuance under employee stock purchase plan 2,543,089 2,896,226 Total 27,666,452 28,773,991 Share Repurchase Program In February 2022, the Board of Directors authorized the Company to purchase up to $400.0 million of common stock of the Company. The Company may repurchase shares from time to time through open market purchases, in privately negotiated transactions or by other means, including through the use of trading plans intended to qualify under Rule 10b5-1. The repurchase program does not obligate the Company to acquire any particular amount of its common stock, and may be suspended or terminated by the Company at any time at its discretion without prior notice. The Company records share repurchases on the settlement date. Repurchased shares are subsequently retired and returned to the status of authorized but unissued. The Company’s policy for share retirements is to allocate the excess between par value and the repurchase price, including costs and fees, to additional paid-in capital. During the nine months ended September 30, 2023, the Company made no repurchases of common stock. As of September 30, 2023, $222.1 million remains available for future purchases of our common stock under the share repurchase program. Equity Incentive Plans The Company's 2020 Equity Incentive Plan authorizes grants of incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock, restricted stock units, and performance awards to eligible participants. Stock Options The following table summarizes stock option activity for the nine months ended September 30, 2023: Number of Options Weighted-Average Exercise Price Per Share Weighted-Average Remaining Contractual Life (years) Aggregate Balances at December 31, 2022 12,547,010 $ 14.65 6.6 $ 77,289 Options granted 2,088,207 15.37 Options exercised (1,058,804) 8.95 Options cancelled and forfeited (561,920) 31.78 Balances at September 30, 2023 13,014,493 14.49 6.3 235,725 Options exercisable – September 30, 2023 8,621,628 8.71 5.0 188,958 Options vested and expected to vest – September 30, 2023 13,014,493 $ 14.49 6.3 $ 235,725 The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying awards and the fair value of the Company’s stock as of September 30, 2023. The aggregate intrinsic value of options exercised for the nine months ended September 30, 2022 and 2023 was $151.7 million and $18.5 million respectively. The weighted-average grant date fair value of options granted during the nine months ended September 30, 2022 and 2023 was $23.29 and $8.06 per share, respectively. The total fair value of options vested for the nine months ended September 30, 2022 and 2023 was $17.3 million and $26.4 million respectively. As of September 30, 2023, total unrecognized stock-based compensation expense related to unvested stock options was $47.5 million, which is expected to be recognized over a remaining weighted-average period of 2.7 years. Restricted Stock Units The Company grants restricted stock units (“RSUs”) to employees and nonemployees. RSUs vest upon satisfaction of a service-based condition, which is generally satisfied over one Number of Shares Weighted-Average Grant Date Fair Value Per Share Unvested at December 31, 2022 6,046,796 $ 51.28 RSUs granted 3,765,967 18.70 RSUs vested (2,247,325) 37.67 RSUs cancelled and forfeited (1,173,870) 63.39 Unvested at September 30, 2023 6,391,568 $ 34.65 As of September 30, 2023, total unrecognized stock-based compensation expense related to outstanding unvested RSUs was $174.0 million, which is expected to be recognized over a remaining weighted-average period of 2.2 years. Restricted Stock In connection with the Prodigy Software, Inc. (“Prodigy”) acquisition in April 2021, 82,201 shares of the Company’s restricted common stock (“restricted stock”) with a fair value of $10.1 million were issued to certain Prodigy employees. The restricted stock is subject to transfer restrictions and a repurchase option and is contingent upon the employees' continued employment with the Company. The restricted stock is subject to restrictions which lapse on a quarterly basis over two years from the time of the Prodigy acquisition. As of September 30, 2023, restricted stock was fully lapsed and there was no unrecognized stock-based compensation expense. The following table summarizes restricted stock activity for the nine months ended September 30, 2023: Number of Shares Weighted-Average Grant Date Fair Value Per Share Unvested at December 31, 2022 10,271 $ 123.33 Vested (10,271) 123.33 Unvested at September 30, 2023 — $ — Performance-based Restricted Stock Units On February 24, 2023, the Company’s Compensation Committee of the Board of Directors approved the cancellation of a performance-based restricted stock unit award (“PRSUs”) that may be settled for 687,500 shares of the Company’s common stock granted to an executive in February 2022. At the time the PRSUs were granted, the PRSUs were intended to be the executive’s primary compensation through calendar year 2029 so that, in connection with the grant of the PRSUs, the executive’s cash compensation was limited to the amount necessary to allow the executive to participate in the broad-based employee benefits generally applicable at the Company. In reaching its decision to cancel the PRSUs, the Compensation Committee extensively considered the purpose of the PRSUs and determined that the grant no longer provided the intended retention and incentive value to the executive. After considering various alternatives and the pros and cons of such alternatives and consulting with its external advisors, the Compensation Committee believed it was in the best interest of the Company and its stockholders to cancel the PRSUs in exchange for the reinstatement of the executive’s cash compensation, including the executive’s annual base salary and eligibility to participate in the Company’s 2023 Executive Bonus Plan with an annual target bonus opportunity equal to 75% of the executive’s annual base salary. Compensation expense associated with the PRSUs was recognized using the straight-line attribution method for each of the nine vesting tranches over the respective derived service period. The weighted-average grant date fair value using the Monte Carlo simulation was $68.76 per share. The Company recognizes stock-based compensation expense for awards subject to market-based vesting conditions regardless of whether these conditions will be achieved or not, and stock-based compensation expense for any such awards is not reversed if the market condition is not met. The cancellation of the grant was treated by the Company as a settlement for no consideration and remaining unrecognized compensation expense of $39.0 million associated with the grant was accelerated and recorded by the Company as part of engineering and product development expense on the condensed consolidated statements of operations and comprehensive loss for the nine months ended September 30, 2023. 2020 Employee Stock Purchase Plan Our employee stock purchase plan (“ESPP”) provides for consecutive six-month offering periods. The offering periods are scheduled to start on the first trading day on or after February 15 and August 15 of each year. The ESPP permits participants to purchase shares in the amount of 85% of the lower of the fair market value of our shares of common stock on the first trading day of the offering period or on the exercise date. During the nine months ended September 30, 2023, 459,459 shares of common stock were purchased under the ESPP. As of September 30, 2023, total unrecognized stock-based compensation expense related to the ESPP was $2.4 million, which is expected to be recognized over a remaining weighted-average period of 0.4 years. Fair Value of Awards Granted In determining the fair value of stock-based awards, the Company uses a Black-Scholes option-pricing model for its options granted and ESPP purchase rights and a Monte Carlo simulation model for its PRSUs. The inputs used for estimating the fair values of options granted, ESPP purchase rights and PRSUs granted during the period include: Fair Value of Common Stock –The fair value of the Company’s common stock is determined by the closing price, on the date of grant, of its common stock, which is traded on the Nasdaq Global Select Market. Expected Term –The expected term represents the period that the Company’s stock options and ESPP purchase rights are expected to be outstanding. We estimate the expected term based on the simplified method, which is the weighted-average time to vesting and the contractual maturity. The expected term for PRSUs is the simulation term, the time period from the valuation date to the end of the performance measurement period. Volatility –Because the Company has not had an active trading market for its common stock for a sufficient period of time, the expected volatility is estimated based on the average volatility for comparable publicly-traded companies, over a period equal to the expected term of the stock option grants. Risk-free Interest Rate –The risk-free interest rate assumption is based on the U.S. Treasury zero coupon issues in effect at the time of grant for periods corresponding with the expected term of the option. Dividends –The Company has never paid dividends on its common stock and does not anticipate paying dividends on common stock for the foreseeable future. Therefore, the Company uses an expected dividend yield of zero. The following assumptions were used to estimate the fair value of options granted: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Expected term (in years) 5.1 – 6.1 5.3 5.1 – 7.0 5.2 – 7.0 Expected volatility 49.66% – 50.73% 53.33% – 53.38% 47.58% – 50.73% 50.96% – 53.38% Risk-free interest rate 3.28% - 4.02% 4.23% - 4.60% 1.70% – 4.02% 3.45% – 4.60% Dividend yield —% —% —% —% The following assumptions were used to estimate the fair value of the February 2022 PRSUs granted: Expected term (in years) 6.9 Expected volatility 48.43% Risk-free interest rate 1.89% Dividend yield 0% The following assumptions were used to estimate the fair value of ESPP purchase rights: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Expected term (in years) 0.5 0.5 0.5 0.5 Expected volatility 179.35% 131.05% 91.98% - 179.35% 97.74% - 131.05% Risk-free interest rate 3.13% 5.55% 0.72% - 3.13% 4.97% - 5.55% Dividend yield —% —% —% —% Stock-Based Compensation The Company recorded stock-based compensation in the following expense categories in its condensed consolidated statements of operations and comprehensive loss for employees and nonemployees: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Sales and marketing $ 3,028 $ 3,231 $ 7,890 $ 5,097 Customer operations 2,682 2,768 6,386 8,744 Engineering and product development 21,726 17,357 53,254 92,725 General, administrative, and other 9,220 12,212 24,505 35,707 Total $ 36,656 $ 35,568 $ 92,035 $ 142,273

Leases

Leases	9 Months Ended
	Sep. 30, 2023
Leases [Abstract]
Leases	LeasesThe Company’s operating leases expire between 2027 and 2032 and are primarily for its corporate headquarters in San Mateo, California and Columbus, Ohio, as well as additional office space in Columbus, Ohio and Austin, Texas. Certain leases have rent abatement, escalating rent payment provisions, lease renewal options, and tenant allowances. Rent expense is recognized on a straight-line basis over the non-cancelable lease term, except when it is reasonably certain that the renewal option will be exercised. For leases where the Company is reasonably certain to exercise a renewal option, such option periods have been included in the determination of the Company’s ROU assets and lease liabilities on our condensed consolidated balance sheets. In connection with the Company’s lease agreements, letters of credit were issued on behalf of the Company for the benefit of the landlord in an aggregate amount of $3.4 million. The letters of credit are secured by certificates of deposit which are included in restricted cash on the condensed consolidated balance sheets. As of September 30, 2023, future minimum lease payments are as follows: Operating Leases Remaining 2023 $ 3,828 2024 17,054 2025 17,544 2026 18,055 2027 17,745 Thereafter 34,815 Total undiscounted lease payments 109,041 Less: Tenant improvement receivables (2,337) Less: Present value adjustment (13,350) Operating lease liabilities $ 93,354 The Company did not have any material finance leases in any period presented. The Company’s operating lease expense consists of rent and variable lease payments. Variable lease payments such as common area maintenance and parking fees, were included in operating expenses. Rent expense for the Company’s short-term leases was immaterial for the periods presented. Operating lease expense was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Rent expense $ 3,961 $ 4,016 $ 11,837 $ 12,062 Variable lease payments $ 936 $ 1,016 $ 2,724 $ 2,936 Supplemental cash flow and non-cash information related to the Company’s operating leases was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Cash paid for amounts included in the measurement of lease liabilities $ 3,197 $ 3,803 $ 7,967 $ 11,263 Supplemental balance sheet information related to the Company’s operating leases was as follows: September 30, 2023 Weighted-average remaining lease term (in years) 6.66 Weighted-average discount rate 3.86%

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments The Company has loan purchase obligations under the Company’s loan agreements with certain lending partners. These lending partners retain ownership of the loans facilitated through Upstart’s platform for three days or longer (the “holding period”) after origination, as required under the respective agreements. The Company has committed to purchase the loans at the conclusion of the required holding period. As of December 31, 2022 and September 30, 2023, the total loan purchase commitment included outstanding principal balance of $17.8 million and $40.2 million, respectively. Contingencies Accounting for contingencies requires the Company to use judgment related to both the likelihood of a loss and the estimate of the amount or range of loss. The Company records a loss contingency when it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated. The Company discloses material contingencies when it believes a loss is not probable but reasonably possible and may voluntarily provide information on additional contingencies. From time to time the Company is subject to, and it is presently involved in, various litigation and legal proceedings arising from the ordinary course of business activities, the outcome of which the Company cannot reasonably determine. Other than the class actions described below, the Company does not believe that it is presently a party to any litigation of which the outcome would individually, or taken together, have a material adverse effect on our business, operating results, cash flows, or financial condition. As of December 31, 2022 and September 30, 2023, no loss contingency has been recorded in connection with legal proceedings. Indemnifications In the ordinary course of business, the Company may provide indemnifications of varying scope and terms to vendors, directors, officers and other parties with respect to certain matters. In addition, the Company has entered into indemnification agreements with directors and certain officers and employees that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors, officers or employees. No demands have been made upon the Company to provide indemnification under such agreements, and thus, there are no claims that the Company is aware of that could have a material effect on the Company’s condensed consolidated financial statements. Repurchases Under the terms of the loan purchase and loan servicing agreements between the Company and institutional investors, as well as in agreements with investors in securitizations and pass-through certificate transactions, the Company may, in certain circumstances, become obligated to repurchase loans from such institutional investors. Generally, these circumstances include the occurrence of verifiable identity theft, the failure of sold loans to meet the terms of certain loan-level representations and warranties that speak as of the time of origination or sale, the failure to comply with other contractual terms with the institutional investors, or a violation of the applicable federal, state, or local lending laws. The maximum potential amount of future payments associated under this obligation is the outstanding balances of the loans sold to the institutional investors, which at December 31, 2022 and September 30, 2023 is $15,551.1 million and $13,040.8 million, respectively. Actual payments made relating to the Company’s repurchase and indemnification obligations were immaterial. The Company did not have material contingent liabilities related to future loan repurchase obligations as of December 31, 2022 and September 30, 2023. These amounts are included in accrued expenses and other liabilities on the Company’s condensed consolidated balance sheets. Legal On May 13, 2022, a purported class action lawsuit was filed in the United States District Court, Northern District of California, captioned Ward v. Upstart Holdings, Inc., et al., Case No. 5:22-cv-02856-BLF (N.D. Cal.) against the Company, the Company’s Chief Executive Officer, and Chief Financial Officer alleging, among other things, that the defendants made false and/or misleading statements or omissions about the Company’s business, operations, and prospects in violation of Section 10(b) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) and Rule 10b-5 promulgated thereunder, as well as Section 20(a) of the Exchange Act. The Ward lawsuit claimed unspecified damages and legal fees. Between May 19, 2022 and June 22, 2022, two additional related purported class action lawsuits were filed in the United States District Court, Northern District of California, captioned Plymouth County Retirement Association v. Upstart Holdings, Inc., et al., Case No. 3:22-cv-02973-WHO (N.D. Cal.) and Zhang v. Upstart Holdings, Inc., et al., Case No. 3:22-cv-03668-JD (N.D. Cal.). On July 7, 2022, a related purported class action lawsuit was filed in the United States District Court, Southern District of Ohio, captioned Handelsbanken Fonder AB v. Upstart Holdings, Inc., et al., Case No. 2:22-cv-02706-SDM-EPD (S.D. Ohio). The Zhang, Plymouth County, and Handelsbanken Fonder actions named the same defendants and made similar allegations to those in the Ward action. On July 11, 2022, plaintiffs in the Zhang and Plymouth County actions filed notices voluntarily dismissing their lawsuits without prejudice. On July 12, 2022, motions to appoint lead plaintiff and lead counsel were filed in both the Ward action and the Handelsbanken Fonder action. On July 26, 2022, plaintiff in the Ward action filed a notice voluntarily dismissing his lawsuit without prejudice, and on July 27, 2022, plaintiff in the Handelsbanken Fonder action filed a notice voluntarily dismissing its lawsuit without prejudice. On July 26, 2022, an additional lawsuit was filed in United States District Court, Southern District of Ohio, captioned Crain v. Upstart Holdings, Inc. et al., Case No. 2:22-cv-02935-ALM-EPD (S.D. Ohio) against the Company, the Company’s Chief Executive Officer, and Chief Financial Officer. The Crain lawsuit makes allegations similar to those in the Handelsbanken Fonder action and alleges that the defendants made false and/or misleading statements or omissions about the Company’s business, operations, and prospects in violation of Section 10(b) of the Exchange Act and Rule 10b-5 promulgated thereunder, as well as Section 20(a) of the Exchange Act. The Crain lawsuit claims unspecified damages and legal fees. On August 16, 2022, the court appointed a lead plaintiff and approved lead counsel in the Crain action. On December 5, 2022, the lead plaintiff filed a consolidated amended complaint, which names the same defendants as the previous complaint, along with two Company executives, as well as Third Point LLC and its CEO and Third Point Ventures LLC and its managing partner (also a former Upstart board member). The consolidated amended complaint brings the same claims as the previous complaint but adds a claim under Section 20A of the Exchange Act. On February 24, 2023, the Upstart defendants filed a motion to dismiss the consolidated amended complaint. On September 29, 2023, the Court issued an order, granting in part and denying in part the Upstart defendants’ motion. The Company believes the remaining claims in the Crain action are without merit and intends to defend itself vigorously. On July 28, 2022, a derivative lawsuit was filed in United States District Court, Southern District of Ohio, captioned OConnor v. Huber et al., Case No. 2:22-cv-02961-EAS-KAJ (S.D. Ohio). The OConnor action includes allegations similar to those in the Crain complaint, and names as defendants each of the Company’s current board members and its Chief Financial Officer. The Company is named as a nominal defendant. The OConnor action includes claims for violation of Section 10(b) of the Exchange Act and Rule 10b-5 promulgated thereunder, breach of fiduciary duty, aiding and abetting breach of fiduciary duty, unjust enrichment, and waste of corporate assets. The OConnor action seeks unspecified monetary damages and an accounting from the individual defendants. The OConnor action also seeks unspecified corporate governance and internal procedure modifications, punitive damages, and legal fees. On October 7, 2022, a second derivative lawsuit was filed in United States District Court, Southern District of Ohio, captioned Chung v. Huber et al., No. 2:22-cv-03620-MHW-CMV (S.D. Ohio). The Chung action includes allegations similar to those in the OConnor complaint, and names as defendants each of the Company’s current board members, a former board member, and its Chief Financial Officer. The Company is named as a nominal defendant. The Chung action includes claims for violation of Section 10(b), 14(a), and 21D of the Exchange Act, breach of fiduciary duties, unjust enrichment, abuse of control, gross mismanagement, and waste of corporate assets. The Chung action seeks unspecified monetary damages, restitution, and attorney’s fees and costs from the individual defendants. It also seeks corporate governance and internal procedure modifications. On December 12, 2022, in response to a joint motion by the parties, the Court consolidated the OConnor and Chung matters, appointed co-lead counsel, and stayed the consolidated case until resolution of the related Crain securities class action. On February 3, 2023, a third derivative lawsuit was filed, in the United States District Court, District of Delaware, captioned Hsu v. Girouard, et al., 1:23-cv-00132-UNA (D. Del.). The Hsu action includes allegations similar to those in the consolidated derivative matter pending in Ohio, and names as defendants each of the Company’s current board members, a former board member, and its Chief Financial Officer. The Company is named as a nominal defendant. The Hsu action includes claims for violation of Section 14(a) of the Exchange Act as well as breach of fiduciary duties, and seeks unspecified monetary damages, restitution, and attorney’s fees and costs from the individual defendants. It also seeks corporate governance and internal procedure modifications. On February 16, 2023, in response to a joint stipulation and proposed order submitted by the parties, the Court stayed the Hsu action until resolution of the related Crain securities class action. On March 8, 2023, a fourth derivative lawsuit was filed, in the United States District Court, District of Delaware, captioned Sornchai et al. v. Girouard, et al., 1:23-cv-00253-MN (D. Del). The Sornchai action includes allegations similar to those in the consolidated derivative matter pending in Ohio, and names as defendants each of the Company’s current board members, a former board member, its Chief Financial Officer, and a Company executive. The Company is named as a nominal defendant. The Sornchai action includes claims for violations of Sections 10(b), 14(a) and 21D of the Exchange Act, breach of fiduciary duties, breach of fiduciary duty through misappropriation of material non-public information, and unjust enrichment, and seeks unspecified monetary damages, restitution, and attorney’s fees and costs from the individual defendants. It also seeks corporate governance and internal procedure modifications. On March 24, 2023, in response to a joint stipulation and proposed order submitted by the parties, the Court stayed the Sornchai action until resolution of the related Crain securities class action. On April 5, 2023, a fifth derivative lawsuit was filed, in the Court of Chancery of the State of Delaware, captioned Okhai v. Girouard, et al., C.A. No. 2023-0401-SG (Del. Ch.). The Okhai action includes allegations similar to those in the consolidated derivative matter pending in Ohio, and names as defendants the Company’s current board members, two former board members, its Chief Financial Officer, and two current or former Company executives, as well as Third Point LLC and Third Point Ventures LLC. The Okhai action includes claims for breach of fiduciary, aiding and abetting such alleged breaches, and unjust enrichment, and seeks equitable and/or injunctive relief, restitution, and attorney’s fees and costs from the individual defendants. On August 3, 3023, in response to a motion to stay by the defendants in the Okhai action, the Court stayed the Okhai action until resolution of the motion to dismiss in the related Crain securities class action. Following the issuance of the September 29, 2023 order on the motion to dismiss in the related Crain securities class action, the parties agreed to a schedule for briefing a motion by defendants to continue the stay, though a hearing date has not yet been set. On October 13, 2023, a sixth derivative lawsuit was filed, in the Court of Chancery of the State of Delaware, captioned Romanyshyn v. Girouard, et al., C.A. No. 2023-1029-NAC (Del. Ch.). The Romanyshyn action includes allegations similar to those in the consolidated derivative matter pending in Ohio, and names as defendants current and former directors and Company executives, as well as Third Point LLC and its CEO, and Third Point Ventures LLC. The Romanyshyn action includes claims for breach of fiduciary, and seeks unspecified monetary damages, restitution, and attorney’s fees and costs from the individual defendants. It also seeks corporate governance and internal procedure modifications.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s effective tax rates for the three and nine months ended September 30, 2022 and 2023, are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Provision for income taxes $ 12 $ 10 $ 55 $ 44 Effective tax rate (0.02) % (0.03) % (0.10) % (0.02) % The Company's tax provision and the resulting effective tax rate for interim periods are determined based upon its estimated annual effective tax rate adjusted for the effect of discrete items arising during the period. The Company's effective tax rate for the three and nine months ended September 30, 2023 remained relatively consistent compared to the same periods in 2022 as the Company continues to maintain a full valuation allowance with residual current year state taxes. The effective tax rate differs from the U.S. statutory tax rate primarily due to the valuation allowance on the Company’s deferred tax assets as it is more likely than not that some or all of these deferred tax assets will not be realized.

Net Loss Per Share

Net Loss Per Share	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Net Loss Per Share	Net Loss Per Share Basic net loss per common share is based on the weighted-average common shares outstanding during the relevant period. Diluted net loss per share is based on the weighted-average common shares outstanding during the relevant period adjusted for the dilutive effect of share-based awards and convertible debt. For periods in which the Company reports net losses, basic and diluted net loss per share are the same because potentially dilutive common shares are not assumed to have been issued if their effect is anti-dilutive. Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Numerator: Net loss $ (56,223) $ (40,315) $ (53,402) $ (197,734) Denominator: Weighted-average common shares outstanding used to calculate net loss per share, basic 81,672,099 84,404,966 83,236,131 83,158,146 Weighted-average common shares outstanding used to calculate net loss per share, diluted 81,672,099 84,404,966 83,236,131 83,158,146 Net loss per share, basic $ (0.69) $ (0.48) $ (0.64) $ (2.38) Net loss per share, diluted $ (0.69) $ (0.48) $ (0.64) $ (2.38) The following securities were excluded from the computation of diluted net loss per share for the periods presented, due to their anti-dilutive effect. These amounts represent the number of instruments outstanding at the end of each respective quarter: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Options to purchase common stock 11,723,427 13,014,493 11,723,427 13,014,493 Unvested RSUs 4,679,719 6,391,568 4,679,719 6,391,568 Unvested PRSUs 687,500 — 687,500 — Purchase rights committed under the ESPP 109,198 191,677 109,198 191,677 Convertible debt 2,318,078 2,318,078 2,318,078 2,318,078 Total 19,517,922 21,915,816 19,517,922 21,915,816

Reorganization Expenses

Reorganization Expenses	9 Months Ended
	Sep. 30, 2023
Reorganizations [Abstract]
Reorganization Expenses	Reorganization Expenses On January 31, 2023, the Company implemented a plan of reorganization (the “January 2023 Plan”). The January 2023 Plan was designed to reduce operating costs, streamline operations and return the Company to profitability. As part of the January 2023 Plan, the Company reduced its workforce by approximately 20%, or 365 employees, and suspended development of its small business loan product. During the nine months ended September 30, 2023, the Company incurred $15.5 million of reorganization expenses in relation to the January 2023 plan, which primarily consisted of severance charges related to employee cash compensation, benefits, and associated taxes. As of September 30, 2023, the Company has made all cash payments to impacted employees. The Company also recognized an impairment expense of $2.6 million for previously capitalized internally developed software costs. In addition to these charges, the Company recognized $2.9 million of one-time non-cash savings related to the reversal of previously expensed stock-based compensation associated with forfeited stock awards for the nine months ended September 30, 2023. During the three months ended September 30, 2023, the Company incurred no additional reorganization expenses.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Pay vs Performance Disclosure
Net loss	$ (40,315)	$ (56,223)	$ (197,734)	$ (53,402)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended	9 Months Ended
	Sep. 30, 2023 shares	Sep. 30, 2023 shares
Trading Arrangements, by Individual
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Dave Girouard [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		Name and title of officer: Dave Girouard, Chief Executive Officer, in his capacity as Trustee of 2008 D&T Girouard Revocable Trust Date of adoption: August 29, 2023 Duration of the trading arrangement: Through December 13, 2024 or earlier if all transactions under the trading arrangement are completed Aggregate number of securities to be sold from time to time: up to 1,000,000 shares
Name	Dave Girouard
Title	Chief Executive Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	August 29, 2023
Arrangement Duration	472 days
Aggregate Available	1,000,000	1,000,000

Description of Business and S_2

Description of Business and Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation	The accompanying unaudited condensed consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements included in our Annual Report on Form 10-K. Certain prior period amounts have been reclassified or disaggregated where appropriate to conform to the current period presentation of such amounts. In the opinion of management, the accompanying condensed consolidated financial statements reflect all adjustments, which include only normal recurring adjustments, necessary to state fairly the Company’s financial position, results of operations, comprehensive loss and cash flows for the periods presented, but are not necessarily indicative of the results of operations to be anticipated of any future annual or interim periods. Certain information and disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to rules and regulations of the Securities and Exchange Commission. Accordingly, the information included in this Quarterly Report on Form 10-Q should be read in conjunction with the consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K for the year ended December 31, 2022.
Basis of Consolidation	The accompanying unaudited condensed consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements included in our Annual Report on Form 10-K. Certain prior period amounts have been reclassified or disaggregated where appropriate to conform to the current period presentation of such amounts. In the opinion of management, the accompanying condensed consolidated financial statements reflect all adjustments, which include only normal recurring adjustments, necessary to state fairly the Company’s financial position, results of operations, comprehensive loss and cash flows for the periods presented, but are not necessarily indicative of the results of operations to be anticipated of any future annual or interim periods. Certain information and disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to rules and regulations of the Securities and Exchange Commission. Accordingly, the information included in this Quarterly Report on Form 10-Q should be read in conjunction with the consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K for the year ended December 31, 2022.
Use of Estimates	Use of Estimates The preparation of the unaudited condensed consolidated financial statements in conformity with GAAP requires that management make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods.
Derivative Financial Instruments	Derivative Financial Instruments The Company evaluates its contracts and financial instruments to determine if these contracts and instruments or their parts meet the definition of derivatives in accordance with the requirements of the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 815, Derivatives and Hedging . Derivatives are recorded on the condensed consolidated balance sheets at fair value with changes in the value recorded in earnings on the condensed consolidated statements of operations and comprehensive loss, and are reported within the net cash used in operating activities in the condensed consolidated statements of cash flows. The
Beneficial Interests	Beneficial InterestsBeneficial interests represent the Company’s right to receive or an obligation to make cash payments to certain loan buyers based on the performance of credit losses of the underlying loan portfolios. The Company evaluates these arrangements to determine if they or their components meet the characteristics of derivative instruments. Beneficial interests that meet such characteristics are reported in accordance with the derivative financial instruments policy. For other beneficial interests that meet the criteria of a debt security, the Company has elected to record the arrangement at fair value and recognize the changes in fair value and other adjustments on the condensed consolidated statements of operations and comprehensive loss.
Consolidated Securitization	Consolidated Securitization The Company elected the measurement alternative under ASC 810, Consolidation , and maximizes the use of observable inputs to estimate the fair value of the financial assets and liabilities of a consolidated securitization entity. Under the measurement alternative, the Company determined that the fair value of the liabilities, which consists of securitization notes and residual certificates issued by the entity, is based on more observable inputs than inputs used to determine the fair value of the assets, which consists of held-for-sale loans. Thus, the fair value of these loans is determined by the sum of the fair value of the related securitization notes and residual certificates. Changes in the fair value of these assets and liabilities are included in the consolidated statements of operations and comprehensive loss. See “ Note 3. Variable Interest Entities ” and “ Note 6. Fair Value Measurement ” for additional information. Consolidated VIEs The Company consolidates variable interest entities (“VIEs”) in which the Company has a variable interest and is determined to be the primary beneficiary. This determination is based on whether the Company has a variable interest (or combination of variable interests) that provides the Company with (a) the power to direct the activities that most significantly impact the VIE’s economic performance and (b) the obligation to absorb losses or right to receive benefits that could be potentially significant to the VIE. The Company continually reassesses whether it is the primary beneficiary of a VIE throughout the entire period the Company is involved with the VIE. Unconsolidated VIEs The Company’s transactions with unconsolidated VIEs include securitizations of unsecured personal whole loans and sales of whole loans to VIEs. While the Company continues to be involved with the unconsolidated VIEs in its role as the sponsor and the servicer of securitization transactions, the Company does not hold a significant economic interest in these entities and has determined that it is not the primary beneficiary of these entities. The Company’s unconsolidated VIEs include entities established as the issuers and grantor trusts for various securitization transactions. In cases where the VIEs are not consolidated and the transfer of the loans from the Company to the securitization trust meets sale accounting criteria, the Company recognizes a gain or loss on sales of loans. The net proceeds of the sale represent the fair value of any assets obtained or liabilities incurred as part of the transaction. The assets are transferred into a trust such that the assets are legally isolated from the creditors of the Company and are not available to satisfy obligations of the Company. These assets can only be used to settle obligations of the underlying securitization trusts. During the three months ended September 30, 2023, the Company exercised a clean up call related to two unconsolidated VIEs and subsequently liquidated the associated entities. A clean up call option allows the Company, as servicer, to repurchase the remaining transferred financial asset once the collateral falls below a predefined level, which represents the point where servicing becomes administratively burdensome. The clean up calls had no material impact on the condensed consolidated financial statements of the Company. The Company’s maximum exposure to loss from its involvement with unconsolidated VIEs represents the estimated loss that would be incurred under severe, hypothetical circumstances, for which the Company believes the possibility is remote. The carrying value of assets that relate to variable interests in unconsolidated VIEs consists of $6.2 million and $2.8 million of securitization notes and residual certificates which are included in other assets on the condensed consolidated balance sheets as of December 31, 2022 and September 30, 2023, respectively. The Company also had $7.1 million and $6.0 million of cash deposits held as reserve accounts for related securitizations, included in other assets on the condensed consolidated balance sheets as of December 31, 2022 and September 30, 2023. For securitization transactions where the Company is not the risk retaining sponsor, and servicing is the only form of continuing involvement, the Company would only experience a loss if it were required to repurchase such a loan due to a breach in representations and warranties and is not able to collect all repayments, refer to “ Note 12. Commitments and Contingencies ” for further information. The investors and the securitization trusts have no direct recourse to the Company’s assets, and holders of the securities issued by the securitization trusts can look only to the assets of the securitization trusts that issued their
Recently Adopted and Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements On January 1, 2023, the Company adopted Accounting Standards Update (“ASU”) 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers, which was issued by the FASB in October 2021. The new guidance requires contract assets and contract liabilities acquired in a business combination to be recognized and measured by the acquirer on the acquisition date in accordance with ASC 606 , Revenue from Contracts with Customers , as if it had originated the contracts. Under the previous business combinations guidance, such assets and liabilities are recognized by the acquirer at fair value on the acquisition date. The ASU will be applied prospectively to business combinations occurring after the adoption date. The adoption of this new standard did not have an impact on the Company's condensed consolidated financial statements or related disclosures. Recently Issued Accounting Pronouncements In October 2023, the FASB issued ASU 2023-06, Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative (the “Update”) . The amendments in this Update clarify or improve current disclosure and presentation requirements of a variety of topics, including ASC 230-10, Statement of Cash Flows , ASC 260-10, Earnings Per Share , ASC 470-10, Debt , and ASC 815-10, Derivatives, and are intended to align requirements under GAAP with those under Regulation S-X or Regulation S-K. The effective date for each amendment in the Update will be the date on which the SEC’s removal of that related disclosure from Regulation S-X or Regulation S-K becomes effective. However, if by June 30, 2027, the SEC has not removed the applicable requirements from Regulation S-X or Regulation S-K, the amendments will not be effective for any entities. Early adoption is prohibited and the amendments should be applied prospectively. The

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2023
Revenue from Contract with Customer [Abstract]
Schedule of Disaggregation of Revenue by Type of Service	The Company disaggregates revenue from fees by type of service for the periods presented as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Revenue from fees, net: Platform and referral fees, net $ 134,786 $ 112,437 $ 618,208 $ 295,859 Servicing and other fees, net 44,562 34,318 133,467 111,726 Total revenue from fees, net $ 179,348 $ 146,755 $ 751,675 $ 407,585
Schedule of Customers Accounting for Greater Than 10% of Accounts Receivable	Customers accounting for greater than 10% of total revenue were as follows: Three Months Ended Nine Months Ended September 30, 2022 2023 2022 2023 Customer A 45% 33% 47% 30% Customer B 26% 32% 29% 31% Customer C * 12% * 11% * Less than 10% Customers accounting for greater than 10% of accounts receivable were as follows: December 31, September 30, 2022 2023 Customer C 27% 15%
Schedule of Gain (Loss) on Loan Servicing Rights	The Company recognized a net gain related to loan servicing rights upon loan sales for the periods presented as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Net gain related to loan servicing rights $ 6,038 $ 3,472 $ 23,770 $ 10,432
Schedule of Collection Agency and Borrower Fees	The Company recognized collection agency fees and borrower fees, which are included in servicing and other fees, net for the periods presented as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Collection agency fees $ 2,790 $ 4,017 $ 7,345 $ 11,685 Borrower fees $ 7,005 $ 7,182 $ 18,125 $ 21,823
Schedule of Components of Interest Income and Fair Value Adjustments, Net	The following table presents components of the interest income and fair value adjustments, net presented in the Company’s condensed consolidated statements of operations and comprehensive loss: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Interest income (1) $ 22,180 $ 37,692 $ 66,288 $ 116,923 Interest expense (1) (3,050) (9,414) (6,322) (20,828) Fair value and other adjustments Unrealized loss, charge-offs, and other adjustments, net (20,069) (37,521) (70,855) (108,175) Realized loss on sale of loans, net (21,176) (2,955) (45,255) (22,255) Total fair value and other adjustments, net (1) (41,245) (40,476) (116,110) (130,430) Total interest income and fair value adjustments, net $ (22,115) $ (12,198) $ (56,144) $ (34,335) (1) Includes interest income, interest expense and fair value adjustments, net related to the consolidated securitization as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Interest income and fair value adjustments, net related to consolidated securitization: Interest income $ — $ 10,048 $ — $ 10,048 Interest expense — (3,754) — (3,754) Fair value and other adjustments Unrealized gain, charge-offs, and other adjustments, net — 367 — 367 Realized loss on sale of loans, net — — — — Total fair value and other adjustments, net — 367 — 367 Total interest income and fair value adjustments, net $ — $ 6,661 $ — $ 6,661

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	9 Months Ended
	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Financial Assets and Liabilities from Variable Interest Entities	The following tables present a summary of financial assets and liabilities from the Company’s involvement with consolidated VIEs: Assets Liabilities Net Assets December 31, 2022 Consolidated securitization $ — $ — $ — Consolidated warehouse entities 488,337 337,269 151,068 Other consolidated VIEs 496,144 561 495,583 Total consolidated VIEs $ 984,481 $ 337,830 $ 646,651 Assets Liabilities Net Assets September 30, 2023 Consolidated securitization $ 205,107 $ 153,782 $ 51,325 Consolidated warehouse entities 551,045 352,435 198,610 Other consolidated VIEs 244,633 1,837 242,796 Total consolidated VIEs $ 1,000,785 $ 508,054 $ 492,731 The following tables summarize the aggregate value of assets and liabilities of unconsolidated VIEs in which the Company holds a variable interest but is not the primary beneficiary: Assets Liabilities Net Assets Maximum Exposure to Losses December 31, 2022 Securitizations and other $ 364,013 $ 265,040 $ 98,973 $ 13,311 Assets Liabilities Net Assets Maximum Exposure to Losses September 30, 2023 Securitizations and other $ 222,125 $ 158,018 $ 64,107 $ 8,758

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Gains (Losses) Recognized on Derivative Instruments Not Designated as Hedging Instruments	The following table presents the notional amount as well as the fair value of interest rate caps, which is reported as part of other assets on the condensed consolidated balance sheets. There were no material derivative financial instruments held by the Company as of December 31, 2022. September 30, 2023 Notional Amount Fair Value Interest rate caps $ 315,992 $ 9,796 The Company recognizes changes in fair value of these instruments in earnings and reports them as part of the interest expense on the condensed consolidated statements of operations and comprehensive loss. The table below presents gains recognized on the interest rate caps during the following periods: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Fair value gains, net on interest rate caps $ — $ 1,504 $ — $ 2,549

Beneficial Interests (Tables)

Beneficial Interests (Tables)	9 Months Ended
	Sep. 30, 2023
Beneficial Interests [Abstract]
Schedule of Beneficial Interests	The following table presents the aggregate unpaid principal balance of the underlying portfolio as well as the fair value of beneficial interests, which are presented as a separate asset line item on the condensed consolidated balance sheets. As of September 30, 2023, beneficial interest liabilities were immaterial and their value is included in other liabilities on the condensed consolidated balance sheets. There were no beneficial interests assets or liabilities held by the Company as of December 31, 2022. September 30, 2023 Unpaid Principal Balance Fair Value Beneficial interests $ 1,227,371 $ 36,974 The Company recognizes these beneficial interests at fair value with changes reported as part of the fair value and other adjustments on the condensed consolidated statements of operations and comprehensive loss . The table below presents losses recognized on beneficial interests during the following periods: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Fair value losses on beneficial interests $ — $ (7,171) $ — $ (9,127)

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value	The following table presents assets and liabilities measured at fair value and categorized in accordance with the fair value hierarchy: December 31, September 30, Level 2022 2023 Assets Loans 3 $ 1,010,421 $ 972,336 Notes receivable and residual certificates 3 6,181 2,786 Loan servicing assets 3 36,467 30,091 Interest rate caps (1) 2 — 9,796 Beneficial interests 3 — 36,974 Total assets $ 1,053,069 $ 1,051,983 Liabilities Loan servicing liabilities 3 $ 3,968 $ 2,393 Payable to securitization note holders 3 — 153,782 Trailing fee liabilities 3 4,852 4,173 Total liabilities $ 8,820 $ 160,348 (1) The fair value of interest rate caps is determined based on the present value of the estimated future cash flows over the contract term using observable market-based inputs as of the valuation date, including implied interest rates.
Schedule of Fair Value by Classes of Loans Held by the Company	The following table presents the fair value of classes of loans included in the Company’s consolidated balance sheets as of December 31, 2022 and September 30, 2023: December 31, September 30, 2022 2023 Loans held-for-sale $ 882,810 $ 632,316 Loans held-for-investment 127,611 143,493 Loans held in consolidated securitization — 196,527 Total $ 1,010,421 $ 972,336
Schedule of Significant Unobservable Inputs	The following table presents quantitative information about the significant unobservable inputs used for the Company’s Level 3 fair value measurements for loans held-for-sale and held-for-investment: December 31, 2022 September 30, 2023 Minimum Maximum Weighted-Average (2) Minimum Maximum Weighted-Average (2) Discount rate 6.36 % 22.28 % 11.87 % 10.22 % 23.06 % 12.17 % Credit risk rate (1) 0.01 % 93.09 % 16.93 % 0.01 % 92.90 % 16.97 % Prepayment rate (1) 0.08 % 93.43 % 40.49 % 0.13 % 93.43 % 37.85 % (1) Expressed as a percentage of the original principal balance of the loans (2) Unobservable inputs were weighted by relative fair value The following table presents quantitative information about the significant unobservable inputs used for the Company’s Level 3 fair value measurements for loans held in consolidated securitization: December 31, 2022 September 30, 2023 Minimum Maximum Weighted-Average (2) Minimum Maximum Weighted-Average (2) Discount rate * * * 10.64 % 23.05 % 12.93 % Credit risk rate (1) * * * 0.61 % 37.70 % 15.56 % Prepayment rate (1) * * * 6.66 % 89.84 % 43.03 % (1) Expressed as a percentage of the original principal balance of the loans (2) Unobservable inputs were weighted by relative fair value The following table presents quantitative information about the significant unobservable inputs used for the Company’s Level 3 fair value measurements of the underlying collateral pools of the assets and liabilities related to securitization transactions: December 31, 2022 September 30, 2023 Minimum Maximum Weighted-Average (2) Minimum Maximum Weighted-Average (2) Notes receivable and residual certificates Discount rate 8.42 % 22.27 % 12.79 % 10.64 % 23.05 % 13.42 % Credit risk rate (1) 0.59 % 50.69 % 18.43 % 0.59 % 50.69 % 17.78 % Prepayment rate (1) 10.90 % 88.73 % 42.66 % 10.90 % 87.53 % 44.13 % Payable to securitization note holders Discount rate * * * 10.64 % 23.05 % 12.93 % Credit risk rate (1) * * * 0.61 % 37.70 % 15.56 % Prepayment rate (1) * * * 6.66 % 89.84 % 43.03 % (1) Expressed as a percentage of the original principal balance of the loans underlying the financial instruments (2) Unobservable inputs were weighted by relative fair value * Not applicable The following table presents quantitative information about the significant unobservable inputs used for the Company’s fair value measurements of beneficial interests as of September 30, 2023: Minimum Maximum Weighted-Average (1) Beneficial interests Discount rate 7.00 % 14.00 % 13.81 % Credit risk rate spread (2) (5.70) % 0.00 % (5.70) % (1) Unobservable inputs were weighted by relative fair value. (2) Expressed as a percentage of cumulative loss expectations as of the valuation date compared to the origination date.
Schedule of Sensitivity Analysis of Fair Value	The following table presents the sensitivity of the fair value of loans held-for-sale and held-for-investment to adverse changes in key assumptions used in the valuation model as of December 31, 2022 and September 30, 2023, respectively. December 31, September 30, 2022 2023 Fair value of loans held-for-sale and held-for-investment $ 1,010,421 $ 775,809 Discount rates 100 basis point increase (11,979) (9,167) 200 basis point increase (23,720) (18,153) Expected credit loss rates on underlying loans 10% adverse change (11,927) (9,739) 20% adverse change (23,852) (19,513) Expected prepayment rates 10% adverse change (2,284) (1,904) 20% adverse change (4,530) (3,763) The following table presents the sensitivity of the fair value of loans in consolidated securitization to adverse changes in key assumptions used in the valuation model as September 30, 2023. No loans were held in consolidated securitization as of December 31, 2022. December 31, September 30, 2022 2023 Fair value of loans held in consolidated securitization $ — $ 196,527 Discount rates 100 basis point increase — (2,660) 200 basis point increase — (5,264) Expected credit loss rates on underlying loans 10% adverse change — (2,758) 20% adverse change — (5,449) Expected prepayment rates 10% adverse change — (2,090) 20% adverse change — (4,142) The following table presents the sensitivity of beneficial interests to adverse changes in key assumptions used in the valuation model as of September 30, 2023. September 30, 2023 Fair value of beneficial interests $ 36,974 Discount rate 100 basis point increase (879) 200 basis point increase (1,725) Expected credit rate spreads on underlying loans 10% adverse change (10,044) 20% adverse change (15,789)
Schedule of Rollforward of Level 3 Assets	The following tables include a rollforward of the loans classified within Level 3 of the fair value hierarchy: Loans Held-for- Loans Held-for-Investment Loans Held in Consolidated Securitization Total Fair value at June 30, 2022 $ 605,319 $ 18,444 $ — $ 623,763 Purchases of loans 333,779 41,402 — 375,181 Sale of loans (232,302) — — (232,302) Purchase of loans for immediate resale 722,080 — — 722,080 Immediate resale of loans (722,080) — — (722,080) Repayments received (43,748) (2,699) — (46,447) Changes in fair value recorded in earnings (16,499) (4,560) — (21,059) Other changes 629 690 — 1,319 Fair value at September 30, 2022 $ 647,178 $ 53,277 $ — $ 700,455 Loans Held-for- Loans Held-for-Investment Loans Held in Consolidated Securitization Total Fair value at December 31, 2021 $ 142,685 $ 109,792 $ — $ 252,477 Reclassification of loans from HFS to HFI 103,679 (103,679) — — Purchases of loans 1,459,544 55,278 — 1,514,822 Sale of loans (866,984) — — (866,984) Purchase of loans for immediate resale 5,519,116 — — 5,519,116 Immediate resale (5,519,116) — — (5,519,116) Repayments received (128,023) (3,737) — (131,760) Changes in fair value recorded in earnings (68,329) (5,047) — (73,376) Other changes 4,606 670 — 5,276 Fair value at September 30, 2022 $ 647,178 $ 53,277 $ — $ 700,455 Loans Held-for- Loans Held-for-Investment Loans Held in Consolidated Securitization Total Fair value at June 30, 2023 $ 689,851 $ 147,714 $ — $ 837,565 Transfer of loans to consolidated securitization (1) (209,968) — 209,968 — Purchases of loans (2) 483,921 32,714 — 516,635 Sale of loans (269,627) — — (269,627) Purchase of loans for immediate resale 342,467 — — 342,467 Immediate resale of loans (342,467) — — (342,467) Repayments received (40,894) (24,757) (12,302) (77,953) Changes in fair value recorded in earnings (20,203) (13,235) (1,139) (34,577) Other changes (764) 1,057 — 293 Fair value at September 30, 2023 $ 632,316 $ 143,493 $ 196,527 $ 972,336 (1) Transfer of loans to consolidated securitization at fair value. (2) Purchase activity includes an immaterial unpaid principal balance related to securitization clean-up calls during the three months ended September 30, 2023. Loans Held-for- Loans Held-for-Investment Loans Held in Consolidated Securitization Total Fair value at December 31, 2022 $ 882,810 $ 127,611 $ — $ 1,010,421 Transfer of loans to consolidated securitization (1) (209,968) — 209,968 — Purchases of loans (2) 1,053,309 121,293 — 1,174,602 Sale of loans (888,019) — — (888,019) Purchase of loans for immediate resale 1,023,426 — — 1,023,426 Immediate resale of loans (1,023,426) — — (1,023,426) Repayments received (149,697) (68,212) (12,302) (230,211) Changes in fair value recorded in earnings (54,767) (40,003) (1,139) (95,909) Other changes (1,352) 2,804 — 1,452 Fair value at September 30, 2023 $ 632,316 $ 143,493 $ 196,527 $ 972,336 (1) Transfer of loans to consolidated securitization at fair value. (2) Purchase activity includes an immaterial unpaid principal balance related to securitization clean-up calls during the nine months ended September 30, 2023. The following tables include a rollforward of the notes receivable and residual certificates and payables to securitization note holders related to securitization transactions classified by the Company within Level 3 of the fair value hierarchy: Notes Receivable and Residual Certificates Payable to Securitization Note Holders Fair value at June 30, 2022 $ 4,698 $ — Repayments and settlements (1,596) — Changes in fair value recorded in earnings 357 — Fair value at September 30, 2022 $ 3,459 $ — Notes Receivable and Residual Certificates Payable to Fair value at December 31, 2021 $ 8,288 $ — Repayments and settlements (5,508) — Changes in fair value recorded in earnings 679 — Fair value at September 30, 2022 $ 3,459 $ — Notes Receivable and Residual Certificates Payable to Fair value at June 30, 2023 $ 3,907 $ — Additions — 165,318 Repayments and settlements (560) (10,016) Changes in fair value recorded in earnings (561) (1,520) Fair value at September 30, 2023 $ 2,786 $ 153,782 Notes Receivable and Residual Certificates Payable to Fair value at December 31, 2022 $ 6,181 $ — Additions — 165,318 Repayments and settlements (3,556) (10,016) Changes in fair value recorded in earnings 161 (1,520) Fair value at September 30, 2023 $ 2,786 $ 153,782 The following tables present a rollforward of beneficial interests: Beneficial Interests Fair value as of June 30, 2023 $ 28,664 Additions 14,719 Changes in fair value recorded in earnings (6,409) Fair value as of September 30, 2023 $ 36,974 Beneficial Interests Fair value as of December 31, 2022 $ — Additions 45,254 Changes in fair value recorded in earnings (8,280) Fair value as of September 30, 2023 $ 36,974
Schedule of Rollforward of Level 3 Liabilities	The following tables include a rollforward of the notes receivable and residual certificates and payables to securitization note holders related to securitization transactions classified by the Company within Level 3 of the fair value hierarchy: Notes Receivable and Residual Certificates Payable to Securitization Note Holders Fair value at June 30, 2022 $ 4,698 $ — Repayments and settlements (1,596) — Changes in fair value recorded in earnings 357 — Fair value at September 30, 2022 $ 3,459 $ — Notes Receivable and Residual Certificates Payable to Fair value at December 31, 2021 $ 8,288 $ — Repayments and settlements (5,508) — Changes in fair value recorded in earnings 679 — Fair value at September 30, 2022 $ 3,459 $ — Notes Receivable and Residual Certificates Payable to Fair value at June 30, 2023 $ 3,907 $ — Additions — 165,318 Repayments and settlements (560) (10,016) Changes in fair value recorded in earnings (561) (1,520) Fair value at September 30, 2023 $ 2,786 $ 153,782 Notes Receivable and Residual Certificates Payable to Fair value at December 31, 2022 $ 6,181 $ — Additions — 165,318 Repayments and settlements (3,556) (10,016) Changes in fair value recorded in earnings 161 (1,520) Fair value at September 30, 2023 $ 2,786 $ 153,782 The following tables include a rollforward of trailing fee liabilities classified by the Company within Level 3 of the fair value hierarchy: Trailing Fee Liabilities Fair value at June 30, 2022 $ 5,446 Issuances 618 Repayments and settlements (816) Changes in fair value recorded in earnings (47) Fair value at September 30, 2022 $ 5,201 Trailing Fee Liabilities Fair value at December 31, 2021 $ 4,315 Issuances 3,404 Repayments and settlements (2,211) Changes in fair value recorded in earnings (307) Fair value at September 30, 2022 $ 5,201 Trailing Fee Liabilities Fair value at June 30, 2023 $ 4,265 Issuances 580 Repayments and settlements (670) Changes in fair value recorded in earnings (2) Fair value at September 30, 2023 $ 4,173 Trailing Fee Liabilities Fair value at December 31, 2022 $ 4,852 Issuances 1,414 Repayments and settlements (2,096) Changes in fair value recorded in earnings 3 Fair value at September 30, 2023 $ 4,173
Schedule of Aggregate Fair Value and Principal Outstanding of All Loans And Loans 90 Days or More Past Due	The following table presents the aggregate fair value and aggregate principal outstanding of all loans and loans that were 90 days or more past due included in the condensed consolidated balance sheets: Loans Loans > 90 Days Past Due December 31, September 30, December 31, September 30, 2022 2023 2022 2023 Outstanding principal balance $ 1,047,714 $ 1,002,387 $ 9,006 $ 12,811 Net fair value and accrued interest adjustments (37,293) (30,051) (7,006) (10,528) Fair value (1) $ 1,010,421 $ 972,336 $ 2,000 $ 2,283 (1) Includes $397.7 million and $379.5 million of auto loans as of December 31, 2022 and September 30, 2023, respectively, of which an immaterial amount is 90 days or more past due for each period presented.
Schedule of Level 3 Fair Value Assumptions for Loan Servicing Assets and Liabilities	The following table presents quantitative information about the significant unobservable inputs used for the Company’s Level 3 fair value measurements for loan servicing assets and liabilities: December 31, 2022 September 30, 2023 Minimum Maximum Weighted-Average (2) Minimum Maximum Weighted-Average (2) Discount rate 13.00 % 20.00 % 17.20 % 13.00 % 20.00 % 16.92 % Credit risk rate (1) 0.03 % 91.76 % 16.22 % 0.05 % 81.10 % 15.04 % Market-servicing rate (3)(4)(5) 0.62 % 3.72 % 0.62 % 0.62 % 3.72 % 0.63 % Prepayment rate (1) 0.53 % 91.99 % 41.19 % 2.17 % 96.90 % 41.57 % (1) Expressed as a percentage of the original principal balance of the loans underlying the servicing arrangement (2) Unobservable inputs were weighted by relative fair value (3) Excludes ancillary fees that would be passed on to a third-party servicer (4) Expressed as a percentage of the outstanding principal balance of the loan (5) Includes personal loans and auto loans
Schedule of Fair Value Sensitivity of Loan Servicing Assets and Liabilities to Adverse Changes in Key Assumptions	The table below presents the fair value sensitivity of loan servicing assets and liabilities to adverse changes in key assumptions. The fair value of loan servicing assets and liabilities is not sensitive to adverse changes in discount rates and prepayment rates as such changes would not result in a significant impact on the fair value as of December 31, 2022 and September 30, 2023, respectively. December 31, September 30, 2022 2023 Fair value of loan servicing assets $ 36,467 $ 30,091 Expected market-servicing rates 10% market-servicing rates increase (9,989) (5,689) 20% market-servicing rates increase (19,950) (16,101) December 31, September 30, 2022 2023 Fair value of loan servicing liabilities $ 3,968 $ 2,393 Expected market-servicing rates 10% market-servicing rates increase 2,303 1,329 20% market-servicing rates increase 4,640 2,702
Schedule of Servicing Liabilities at Fair Value Rollforward	The following tables present a rollforward of the loan servicing assets and liabilities classified by the Company within Level 3 of the fair value hierarchy: Loan Servicing Assets Loan Servicing Liabilities Fair value at June 30, 2022 $ 35,171 $ 6,366 Sale of loans 6,048 9 Changes in fair value recorded in earnings (4,182) (1,565) Fair value at September 30, 2022 $ 37,037 $ 4,810 Loan Servicing Assets Loan Servicing Liabilities Fair value at December 31, 2021 $ 18,388 $ 8,780 Sale of loans 26,066 2,296 Changes in fair value recorded in earnings (7,417) (6,266) Fair value at September 30, 2022 $ 37,037 $ 4,810 Loan Servicing Assets Loan Servicing Liabilities Fair value at June 30, 2023 $ 33,339 $ 2,577 Sale of loans 3,475 3 Changes in fair value recorded in earnings (6,723) (187) Fair value at September 30, 2023 $ 30,091 $ 2,393 Loan Servicing Assets Loan Servicing Liabilities Fair value at December 31, 2022 $ 36,467 $ 3,968 Sale of loans 10,512 80 Changes in fair value recorded in earnings (16,888) (1,655) Fair value at September 30, 2023 $ 30,091 $ 2,393
Schedule of Servicing Assets at Fair Value Rollforward	The following tables present a rollforward of the loan servicing assets and liabilities classified by the Company within Level 3 of the fair value hierarchy: Loan Servicing Assets Loan Servicing Liabilities Fair value at June 30, 2022 $ 35,171 $ 6,366 Sale of loans 6,048 9 Changes in fair value recorded in earnings (4,182) (1,565) Fair value at September 30, 2022 $ 37,037 $ 4,810 Loan Servicing Assets Loan Servicing Liabilities Fair value at December 31, 2021 $ 18,388 $ 8,780 Sale of loans 26,066 2,296 Changes in fair value recorded in earnings (7,417) (6,266) Fair value at September 30, 2022 $ 37,037 $ 4,810 Loan Servicing Assets Loan Servicing Liabilities Fair value at June 30, 2023 $ 33,339 $ 2,577 Sale of loans 3,475 3 Changes in fair value recorded in earnings (6,723) (187) Fair value at September 30, 2023 $ 30,091 $ 2,393 Loan Servicing Assets Loan Servicing Liabilities Fair value at December 31, 2022 $ 36,467 $ 3,968 Sale of loans 10,512 80 Changes in fair value recorded in earnings (16,888) (1,655) Fair value at September 30, 2023 $ 30,091 $ 2,393

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Acquired Intangible Assets	The gross and net carrying values and accumulated amortization are as follows: Developed Technology December 31, 2022 September 30, Gross carrying amount $ 9,400 $ 9,400 Accumulated amortization (5,483) (7,833) Net carrying value $ 3,917 $ 1,567 Customer Relationships December 31, 2022 September 30, Gross carrying amount $ 13,700 $ 13,700 Accumulated amortization (1,998) (2,854) Net carrying value $ 11,702 $ 10,846
Schedule of Expected Future Amortization Expense	Expected future amortization expense for intangible assets as of September 30, 2023 is as follows: Fiscal Years: Remaining 2023 $ 1,069 2024 1,925 2025 1,142 2026 1,142 2027 1,142 Thereafter 5,993 Total $ 12,413

Balance Sheet Components (Table

Balance Sheet Components (Tables)	9 Months Ended
	Sep. 30, 2023
Other Assets [Abstract]
Schedule of Other Assets	Other assets consisted of the following: December 31, September 30, 2022 2023 Servicing fees and other receivables $ 46,652 $ 41,191 Loan servicing assets (at fair value) 36,467 30,091 Prepaid expenses 16,740 21,052 Intangible assets, net (1) 15,631 12,425 Interest rate caps (2) — 9,796 Deposits 10,002 8,666 Notes receivable and residual certificates (at fair value) 6,181 2,786 Other assets 22,678 17,773 Total other assets $ 154,351 $ 143,780 (1) Refer to “ Note 7. Goodwill and Intangible Assets ” for further information. (2) Refer to “ Note 4. Derivative Financial Instruments” for further information.
Schedule of Property, Equipment, and Software	Property, equipment, and software, net consisted of the following: December 31, September 30, 2022 2023 Internally developed software $ 37,783 $ 52,808 Leasehold improvements 13,074 14,050 Computer and networking equipment 6,049 6,054 Furniture and fixtures 4,421 4,736 Total property, equipment, and software 61,327 77,648 Accumulated depreciation and amortization (17,159) (29,638) Total property, equipment, and software, net $ 44,168 $ 48,010
Schedule of Accrued Expenses and Other Liabilities	Accrued expenses and other liabilities consisted of the following: December 31, September 30, 2022 2023 Accrued expenses $ 23,506 $ 19,689 Accrued payroll 21,825 21,303 Loan servicing liabilities (at fair value) 3,968 2,393 Trailing fee liability (at fair value) 4,852 4,173 Other liabilities 12,795 4,295 Total accrued expenses and other liabilities $ 66,946 $ 51,853

Borrowings (Tables)

Borrowings (Tables)	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Schedule of Aggregate Principal Outstanding of All Debt	The following table presents the aggregate principal outstanding of all debt mentioned in this note that are included in the condensed consolidated balance sheets: Borrowings December 31, September 30, 2022 2023 Warehouse credit facilities $ 336,452 $ 351,154 Convertible senior notes 661,250 661,250 Total payments due 997,702 1,012,404 Unamortized debt discount (11,308) (9,012) Total borrowings $ 986,394 $ 1,003,392
Schedule of Assets Pledge as Collateral	The following table includes the aggregate balances held by ULT that were pledged as collateral for the ULT Warehouse Credit Facility and included in loans at fair value and restricted cash in the condensed consolidated balance sheets: ULT Warehouse Credit Facility December 31, 2022 September 30, Outstanding borrowings $ 163,773 $ 170,303 Aggregate outstanding principal of loans pledged as collateral 228,895 236,822 Aggregate fair value of loans purchased and held by ULT 256,024 241,049 Restricted cash pledged as collateral $ 8,547 $ 5,067 The following table includes the aggregate balances held by UAWT that were pledged as collateral for the UAWT Warehouse Credit Facility and included in loans at fair value and restricted cash in the condensed consolidated balance sheets as of December 31, 2022 and September 30, 2023. UAWT Warehouse Credit Facility December 31, 2022 September 30, 2023 Outstanding borrowings $ 172,679 $ 180,851 Aggregate outstanding principal of loans pledged as collateral 221,847 308,338 Aggregate fair value of loans purchased and held by UAWT 216,539 296,694 Restricted cash pledged as collateral $ 843 $ 360
Schedule of Maturities of All Borrowings	The following table summarizes the aggregate amount of maturities of all borrowings as of September 30, 2023: September 30, Remaining 2023 $ — 2024 — 2025 180,851 2026 831,553 2027 — Thereafter — Total $ 1,012,404

Stockholders_ Equity (Tables)

Stockholders’ Equity (Tables)	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Schedule of Shares and Warrants Reserved for Issuance	In December 2020, the Company's amended and restated certificate of incorporation became effective, which authorizes the issuance of 700,000,000 shares of common stock with a par value of $0.0001 per share. Shares of common stock reserved for issuance, on an as-converted basis, are as follows: December 31, September 30, 2022 2023 Options issued and outstanding 12,547,010 13,014,493 Restricted stock units outstanding 6,046,796 6,391,568 Performance-based restricted stock unit outstanding 687,500 — Shares available for future issuance under 2020 plan 5,842,057 6,471,704 Shares available for issuance under employee stock purchase plan 2,543,089 2,896,226 Total 27,666,452 28,773,991
Schedule of Stock Option Activity	The following table summarizes stock option activity for the nine months ended September 30, 2023: Number of Options Weighted-Average Exercise Price Per Share Weighted-Average Remaining Contractual Life (years) Aggregate Balances at December 31, 2022 12,547,010 $ 14.65 6.6 $ 77,289 Options granted 2,088,207 15.37 Options exercised (1,058,804) 8.95 Options cancelled and forfeited (561,920) 31.78 Balances at September 30, 2023 13,014,493 14.49 6.3 235,725 Options exercisable – September 30, 2023 8,621,628 8.71 5.0 188,958 Options vested and expected to vest – September 30, 2023 13,014,493 $ 14.49 6.3 $ 235,725
Schedule of Restricted Stock Units and Restricted Stock	The following table summarizes RSU activity for the nine months ended September 30, 2023: Number of Shares Weighted-Average Grant Date Fair Value Per Share Unvested at December 31, 2022 6,046,796 $ 51.28 RSUs granted 3,765,967 18.70 RSUs vested (2,247,325) 37.67 RSUs cancelled and forfeited (1,173,870) 63.39 Unvested at September 30, 2023 6,391,568 $ 34.65 The following table summarizes restricted stock activity for the nine months ended September 30, 2023: Number of Shares Weighted-Average Grant Date Fair Value Per Share Unvested at December 31, 2022 10,271 $ 123.33 Vested (10,271) 123.33 Unvested at September 30, 2023 — $ —
Schedule of Stock Options Fair Value Assumptions	The following assumptions were used to estimate the fair value of options granted: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Expected term (in years) 5.1 – 6.1 5.3 5.1 – 7.0 5.2 – 7.0 Expected volatility 49.66% – 50.73% 53.33% – 53.38% 47.58% – 50.73% 50.96% – 53.38% Risk-free interest rate 3.28% - 4.02% 4.23% - 4.60% 1.70% – 4.02% 3.45% – 4.60% Dividend yield —% —% —% —%
Schedule of Employee Stock Purchase Plan Fair Value Assumptions	The following assumptions were used to estimate the fair value of the February 2022 PRSUs granted: Expected term (in years) 6.9 Expected volatility 48.43% Risk-free interest rate 1.89% Dividend yield 0% The following assumptions were used to estimate the fair value of ESPP purchase rights: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Expected term (in years) 0.5 0.5 0.5 0.5 Expected volatility 179.35% 131.05% 91.98% - 179.35% 97.74% - 131.05% Risk-free interest rate 3.13% 5.55% 0.72% - 3.13% 4.97% - 5.55% Dividend yield —% —% —% —%
Schedule of Stock-based Compensation Expense	The Company recorded stock-based compensation in the following expense categories in its condensed consolidated statements of operations and comprehensive loss for employees and nonemployees: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Sales and marketing $ 3,028 $ 3,231 $ 7,890 $ 5,097 Customer operations 2,682 2,768 6,386 8,744 Engineering and product development 21,726 17,357 53,254 92,725 General, administrative, and other 9,220 12,212 24,505 35,707 Total $ 36,656 $ 35,568 $ 92,035 $ 142,273

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2023
Leases [Abstract]
Schedule of Future Minimum Lease Payments	As of September 30, 2023, future minimum lease payments are as follows: Operating Leases Remaining 2023 $ 3,828 2024 17,054 2025 17,544 2026 18,055 2027 17,745 Thereafter 34,815 Total undiscounted lease payments 109,041 Less: Tenant improvement receivables (2,337) Less: Present value adjustment (13,350) Operating lease liabilities $ 93,354
Schedule of Operating Lease Expense and Supplemental Cash and Non-cash Information	Operating lease expense was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Rent expense $ 3,961 $ 4,016 $ 11,837 $ 12,062 Variable lease payments $ 936 $ 1,016 $ 2,724 $ 2,936 Supplemental cash flow and non-cash information related to the Company’s operating leases was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Cash paid for amounts included in the measurement of lease liabilities $ 3,197 $ 3,803 $ 7,967 $ 11,263 Supplemental balance sheet information related to the Company’s operating leases was as follows: September 30, 2023 Weighted-average remaining lease term (in years) 6.66 Weighted-average discount rate 3.86%

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Schedule of Effective Tax Rates	The Company’s effective tax rates for the three and nine months ended September 30, 2022 and 2023, are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Provision for income taxes $ 12 $ 10 $ 55 $ 44 Effective tax rate (0.02) % (0.03) % (0.10) % (0.02) %

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Schedule of Net Loss Per Share	For periods in which the Company reports net losses, basic and diluted net loss per share are the same because potentially dilutive common shares are not assumed to have been issued if their effect is anti-dilutive. Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Numerator: Net loss $ (56,223) $ (40,315) $ (53,402) $ (197,734) Denominator: Weighted-average common shares outstanding used to calculate net loss per share, basic 81,672,099 84,404,966 83,236,131 83,158,146 Weighted-average common shares outstanding used to calculate net loss per share, diluted 81,672,099 84,404,966 83,236,131 83,158,146 Net loss per share, basic $ (0.69) $ (0.48) $ (0.64) $ (2.38) Net loss per share, diluted $ (0.69) $ (0.48) $ (0.64) $ (2.38)
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following securities were excluded from the computation of diluted net loss per share for the periods presented, due to their anti-dilutive effect. These amounts represent the number of instruments outstanding at the end of each respective quarter: Three Months Ended September 30, Nine Months Ended September 30, 2022 2023 2022 2023 Options to purchase common stock 11,723,427 13,014,493 11,723,427 13,014,493 Unvested RSUs 4,679,719 6,391,568 4,679,719 6,391,568 Unvested PRSUs 687,500 — 687,500 — Purchase rights committed under the ESPP 109,198 191,677 109,198 191,677 Convertible debt 2,318,078 2,318,078 2,318,078 2,318,078 Total 19,517,922 21,915,816 19,517,922 21,915,816

Revenue - Schedule of Disaggreg

Revenue - Schedule of Disaggregation of Revenue by Type of Service (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Revenue from fees, net	$ 146,755	$ 179,348	$ 407,585	$ 751,675
Platform and referral fees, net
Disaggregation of Revenue [Line Items]
Revenue from fees, net	112,437	134,786	295,859	618,208
Servicing and other fees, net
Disaggregation of Revenue [Line Items]
Revenue from fees, net	$ 34,318	$ 44,562	$ 111,726	$ 133,467

Revenue - Narrative (Details)

Revenue - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Trailing fee liabilities	$ 4,200		$ 4,200		$ 4,900
Servicing fees and other receivables	41,191		41,191		46,652
Contract costs capitalized	$ 2,700		$ 2,700		2,600
Loans on non-accrual status	120 days		120 days
Accrued interest income	$ 12,000		$ 12,000		12,800
Amounts received from borrowers for previously charged-off loan	2,600	$ 0	4,600	$ 0
Platform and referral fees, net
Disaggregation of Revenue [Line Items]
Loan premium and loan trailing fees recognized	2,200	$ 6,100	5,600	$ 20,900
Servicing fees and other receivables	$ 19,800		$ 19,800		$ 31,100
Capitalized cost amortization term	3 years		3 years

Revenue - Schedule of Customers

Revenue - Schedule of Customers Accounting for Greater Than 10% of Accounts Receivable (Details) - Customer Concentration Risk	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Customer A | Revenue Benchmark
Disaggregation of Revenue [Line Items]
Concentration risk (in percent)	33%	45%	30%	47%
Customer B | Revenue Benchmark
Disaggregation of Revenue [Line Items]
Concentration risk (in percent)	32%	26%	31%	29%
Customer C | Revenue Benchmark
Disaggregation of Revenue [Line Items]
Concentration risk (in percent)	12%		11%
Customer C | Accounts Receivable
Disaggregation of Revenue [Line Items]
Concentration risk (in percent)			15%		27%

Revenue - Schedule of Gain (los

Revenue - Schedule of Gain (loss) on Loan Servicing Rights (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenue from Contract with Customer [Abstract]
Net gain related to loan servicing rights	$ 3,472	$ 6,038	$ 10,432	$ 23,770

Revenue - Schedule of Collectio

Revenue - Schedule of Collection Agency and Borrower Fees (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Revenue from fees, net	$ 146,755	$ 179,348	$ 407,585	$ 751,675
Collection agency fees
Disaggregation of Revenue [Line Items]
Revenue from fees, net	4,017	2,790	11,685	7,345
Borrower fees
Disaggregation of Revenue [Line Items]
Revenue from fees, net	$ 7,182	$ 7,005	$ 21,823	$ 18,125

Revenue - Schedule of Component

Revenue - Schedule of Components of Interest Income and Fair Value Adjustments, Net (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Interest income	[1]	$ 37,692	$ 22,180	$ 116,923	$ 66,288
Interest expense	[1]	(9,414)	(3,050)	(20,828)	(6,322)
Unrealized gain, charge-offs, and other adjustments, net		(37,521)	(20,069)	(108,175)	(70,855)
Realized loss on sale of loans, net		(2,955)	(21,176)	(22,255)	(45,255)
Total fair value and other adjustments, net	[1]	(40,476)	(41,245)	(130,430)	(116,110)
Total interest income and fair value adjustments, net		(12,198)	(22,115)	(34,335)	(56,144)
Variable Interest Entity, Primary Beneficiary
Disaggregation of Revenue [Line Items]
Interest income		10,048	0	10,048	0
Interest expense		(3,754)	0	(3,754)	0
Unrealized gain, charge-offs, and other adjustments, net		367	0	367	0
Realized loss on sale of loans, net		0	0	0	0
Total fair value and other adjustments, net		367	0	367	0
Total interest income and fair value adjustments, net		$ 6,661	$ 0	$ 6,661	$ 0
[1] Balances for three and nine months ended September 30, 2023 include amounts related to the consolidated securitization. Refer to “ Note 2. Revenue ” for details.

Variable Interest Entities - Sc

Variable Interest Entities - Schedule of Financial Assets and Liabilities from Variable Interest Entities (Details) - USD ($) $ in Thousands		Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Variable Interest Entity [Line Items]
Assets	[1]	$ 2,001,779		$ 1,936,054
Liabilities	[1]	1,361,015		1,263,619
Net Assets		640,764	$ 638,145	672,435	$ 718,568	$ 757,071	$ 807,078
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Assets		1,000,785		984,481
Liabilities		508,054		337,830
Net Assets		492,731		646,651
Variable Interest Entity, Primary Beneficiary | Consolidated securitization
Variable Interest Entity [Line Items]
Assets		205,107		0
Liabilities		153,782		0
Net Assets		51,325		0
Variable Interest Entity, Primary Beneficiary | Consolidated warehouse entities
Variable Interest Entity [Line Items]
Assets		551,045		488,337
Liabilities		352,435		337,269
Net Assets		198,610		151,068
Variable Interest Entity, Primary Beneficiary | Other consolidated VIEs
Variable Interest Entity [Line Items]
Assets		244,633		496,144
Liabilities		1,837		561
Net Assets		242,796		495,583
Variable Interest Entity, Not Primary Beneficiary | Securitizations and other
Variable Interest Entity [Line Items]
Assets		222,125		364,013
Liabilities		158,018		265,040
Net Assets		64,107		98,973
Maximum Exposure to Losses		$ 8,758		$ 13,311
[1]The following table presents information on assets and liabilities related to variable interest entities (“VIEs”) that are consolidated by Upstart Holdings, Inc. at December 31, 2022 and September 30, 2023. The assets in the table below may only be used to settle obligations of consolidated VIEs and are in excess of those obligations. The holders of the beneficial interests do not have recourse to the general credit of Upstart Holdings, Inc. The assets and liabilities in the table below include third-party assets and liabilities of consolidated VIEs and exclude intercompany balances that eliminate in consolidation. December 31, September 30, 2022 2023 Assets Cash $ 838 $ 762 Restricted cash 13,147 23,888 Loans (at fair value) 958,822 964,917 Other assets (includes $2,244 and $10,051 at fair value as of December 31, 2022 and September 30, 2023, respectively) 11,674 11,218 Total assets $ 984,481 $ 1,000,785 Liabilities Payable to investors $ — $ 1,216 Borrowings 336,452 351,169 Payable to securitization note holders (at fair value) — 153,782 Accrued expenses and other liabilities 1,378 1,887 Total liabilities 337,830 508,054 Total net assets $ 646,651 $ 492,731

Variable Interest Entities - Na

Variable Interest Entities - Narrative (Details) $ in Thousands			3 Months Ended	9 Months Ended
		Jul. 06, 2023 USD ($)	Sep. 30, 2023 USD ($) variable_interest_entity	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Variable Interest Entity [Line Items]
Net cash proceeds				$ 165,318	$ 0
Exercised a clean up | variable_interest_entity			2
Financing Receivable, after Allowance for Credit Loss	[1]		$ 972,336	972,336		$ 1,010,421
Restricted cash			98,447	98,447		110,056
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Restricted cash			6,000	6,000		7,100
Variable Interest Entity, Not Primary Beneficiary | Notes receivable and residual certificates (at fair value)
Variable Interest Entity [Line Items]
Financing Receivable, after Allowance for Credit Loss						$ 6,200
Notes receivable and residual certificates			$ 2,800	$ 2,800
Variable Interest Entity, Not Primary Beneficiary | Consolidated securitization
Variable Interest Entity [Line Items]
Variable Interest Entity, Primary Beneficiary, Maximum Loss Exposure, Amount		$ 204,700
Weighted average coupon yield		9.20%
Net cash proceeds		$ 165,300
[1] Includes $196.5 million as of September 30, 2023 of loans, at fair value, contributed as collateral for the consolidated securitization. Refer to “ Note 6. Fair Value Measurement ” for details.

Derivative Financial Instrume_3

Derivative Financial Instruments - Narrative (Details) - USD ($)	Sep. 30, 2023	Jun. 30, 2023	Feb. 28, 2023	Dec. 31, 2022
Derivative [Line Items]
Derivative financial instruments	$ 9,796,000			$ 0
Interest rate caps
Derivative [Line Items]
Interest cap rate		3.25%	3%
Derivative financial instruments	$ 9,796,000

Derivative Financial Instrume_4

Derivative Financial Instruments - Schedule Of Gains (Losses) Recognized On Derivative Instruments Not Designated As Hedging Instruments (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Derivative [Line Items]
Fair Value	$ 9,796,000		$ 9,796,000		$ 0
Interest rate caps
Derivative [Line Items]
Notional Amount	315,992,000		315,992,000
Fair Value	9,796,000		9,796,000
Fair value gains, net on interest rate caps	$ 1,504,000	$ 0	$ 2,549,000	$ 0

Beneficial Interests - Narrativ

Beneficial Interests - Narrative (Details) $ in Millions	Sep. 30, 2023 USD ($)
Beneficial Interests [Abstract]
Maximum exposure to loss	$ 66.1

Beneficial Interests - Schedule

Beneficial Interests - Schedule of Beneficial Interest Liabilities (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Schedule Of Beneficial Interest [Line Items]
Unpaid Principal Balance	$ 1,227,371,000		$ 1,227,371,000
Fair Value	36,974,000		36,974,000		$ 0
Beneficial Interests
Schedule Of Beneficial Interest [Line Items]
Fair value losses on beneficial interests	$ (7,171,000)	$ 0	$ (9,127,000)	$ 0

Fair Value Measurement - Schedu

Fair Value Measurement - Schedule of Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Assets
Loans	$ 972,336	$ 1,010,421
Loan servicing assets	30,091	36,467
Liabilities
Loan servicing liabilities	2,393	3,968
Payable to securitization note holders	153,782	0
Trailing fee liabilities	4,200	4,900
Fair Value, Inputs, Level 3
Assets
Loans	972,336	1,010,421
Notes receivable and residual certificates	2,786	6,181
Loan servicing assets	30,091	36,467
Beneficial interests	36,974	0
Total assets	1,051,983	1,053,069
Liabilities
Loan servicing liabilities	2,393	3,968
Payable to securitization note holders	153,782	0
Trailing fee liabilities	4,173	4,852
Total liabilities	160,348	8,820
Fair Value, Inputs, Level 2
Assets
Interest rate caps	$ 9,796	$ 0

Fair Value Measurement - Sche_2

Fair Value Measurement - Schedule of Fair Value of classes of Loans Held by the Company (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held in consolidated securitization	$ 196,500
Total assets	972,336	$ 1,010,421
Fair Value, Inputs, Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale	632,316	882,810
Loans held-for-investment	143,493	127,611
Loans held in consolidated securitization	196,527	0
Total assets	$ 972,336	$ 1,010,421

Fair Value Measurement - Narrat

Fair Value Measurement - Narrative (Details) - USD ($)	Sep. 30, 2023	Dec. 31, 2022
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans on non-accrual status	120 days
Charges-off loans	120 days
Payable to securitization note holders (at fair value)	$ 153,782,000	$ 0
Beneficial interests (at fair value)	36,974,000	0
Fair Value, Inputs, Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Notes receivable and residual certificates	2,786,000	6,181,000
Payable to securitization note holders (at fair value)	153,782,000	$ 0
Impact of 100 point increase in discount rate	2,200,000
Impact of 200 point increase in discount rate	4,300,000
Beneficial interests (at fair value)	$ 36,974,000
Fair Value, Inputs, Level 3 | Minimum | Discount rate | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	10.22%	6.36%
Trailing fees liability, measurement input	10.22%
Fair Value, Inputs, Level 3 | Minimum | Credit risk rate | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	0.01%	0.01%
Trailing fees liability, measurement input	0.01%
Fair Value, Inputs, Level 3 | Maximum | Discount rate | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	23.06%	22.28%
Trailing fees liability, measurement input	23.06%
Fair Value, Inputs, Level 3 | Maximum | Credit risk rate | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	92.90%	93.09%
Trailing fees liability, measurement input	92.90%

Fair Value Measurement - Sche_3

Fair Value Measurement - Schedule of Significant Unobservable Inputs (Details) - Valuation Technique, Discounted Cash Flow	Sep. 30, 2023	Dec. 31, 2022
Minimum | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Beneficial interests	7%
Minimum | Credit risk rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Beneficial interests	(5.70%)
Minimum | Fair Value, Inputs, Level 3 | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	10.22%	6.36%
Loans held in consolidated collateralization	0.1064
Notes receivable and residual certificates	0.1064	0.0842
Payable to securitization note holders	0.1064
Minimum | Fair Value, Inputs, Level 3 | Credit risk rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	0.01%	0.01%
Loans held in consolidated collateralization	0.0061
Notes receivable and residual certificates	0.0059	0.0059
Payable to securitization note holders	0.0061
Minimum | Fair Value, Inputs, Level 3 | Prepayment rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	0.13%	0.08%
Loans held in consolidated collateralization	0.0666
Notes receivable and residual certificates	0.1090	0.1090
Payable to securitization note holders	0.0666
Maximum | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Beneficial interests	14%
Maximum | Credit risk rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Beneficial interests	0%
Maximum | Fair Value, Inputs, Level 3 | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	23.06%	22.28%
Loans held in consolidated collateralization	0.2305
Notes receivable and residual certificates	0.2305	0.2227
Payable to securitization note holders	0.2305
Maximum | Fair Value, Inputs, Level 3 | Credit risk rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	92.90%	93.09%
Loans held in consolidated collateralization	0.3770
Notes receivable and residual certificates	0.5069	0.5069
Payable to securitization note holders	0.3770
Maximum | Fair Value, Inputs, Level 3 | Prepayment rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	93.43%	93.43%
Loans held in consolidated collateralization	0.8984
Notes receivable and residual certificates	0.8753	0.8873
Payable to securitization note holders	0.8984
Weighted Average | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Beneficial interests	13.81%
Weighted Average | Credit risk rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Beneficial interests	(5.70%)
Weighted Average | Fair Value, Inputs, Level 3 | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	12.17%	11.87%
Loans held in consolidated collateralization	0.1293
Notes receivable and residual certificates	0.1342	0.1279
Payable to securitization note holders	0.1293
Weighted Average | Fair Value, Inputs, Level 3 | Credit risk rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	16.97%	16.93%
Loans held in consolidated collateralization	0.1556
Notes receivable and residual certificates	0.1778	0.1843
Payable to securitization note holders	0.1556
Weighted Average | Fair Value, Inputs, Level 3 | Prepayment rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans receivable	37.85%	40.49%
Loans held in consolidated collateralization	0.4303
Notes receivable and residual certificates	0.4413	0.4266
Payable to securitization note holders	0.4303

Fair Value Measurement - Sche_4

Fair Value Measurement - Schedule of Sensitivity Analysis of Fair Value (Details) - USD ($)	Sep. 30, 2023	Dec. 31, 2022
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of loans	$ 972,336,000	$ 1,010,421,000
Fair value of beneficial interests	36,974,000	0
Loans Held For Sale And Investment
Discount rates
100 basis point increase	(9,167,000)	(11,979,000)
200 basis point increase	(18,153,000)	(23,720,000)
Expected credit loss rates on underlying loans
10% adverse change	(9,739,000)	(11,927,000)
20% adverse change	(19,513,000)	(23,852,000)
Expected prepayment rates
10% adverse change	(1,904,000)	(2,284,000)
20% adverse change	(3,763,000)	(4,530,000)
Loans Held in Consolidated Securitization
Discount rates
100 basis point increase	(2,660,000)	0
200 basis point increase	(5,264,000)	0
Expected credit loss rates on underlying loans
10% adverse change	(2,758,000)	0
20% adverse change	(5,449,000)	0
Expected prepayment rates
10% adverse change	(2,090,000)	0
20% adverse change	(4,142,000)	0
Beneficial Interests
Discount rates
100 basis point increase	(879,000)
200 basis point increase	(1,725,000)
Expected credit loss rates on underlying loans
10% adverse change	(10,044,000)
20% adverse change	(15,789,000)
Fair Value, Inputs, Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of loans	972,336,000	1,010,421,000
Fair value of beneficial interests	36,974,000
Fair Value, Inputs, Level 3 | Loans Held For Sale And Investment
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of loans	775,809,000	1,010,421,000
Fair Value, Inputs, Level 3 | Loans Held in Consolidated Securitization
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of loans	$ 196,527,000	$ 0

Fair Value Measurement - Sche_5

Fair Value Measurement - Schedule of Rollforward of Level 3 Assets (Details) - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Other changes
Loans (at fair value)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	837,565	$ 623,763	$ 1,010,421	$ 252,477
Transfer of loans to consolidated securitization	0		0
Reclassification of loans from HFS to HFI				0
Purchases of loans	516,635	375,181	1,174,602	1,514,822
Sale of loans	(269,627)	(232,302)	(888,019)	(866,984)
Purchase of loans for immediate resale	342,467	722,080	1,023,426	5,519,116
Immediate resale of loans	(342,467)	(722,080)	(1,023,426)	(5,519,116)
Repayments received	(77,953)	(46,447)	(230,211)	(131,760)
Changes in fair value recorded in earnings	(34,577)	(21,059)	(95,909)	(73,376)
Other changes	293	1,319	1,452	5,276
Fair value, ending balance	972,336	700,455	972,336	700,455
Loans Held-for- Sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	689,851	605,319	882,810	142,685
Transfer of loans to consolidated securitization	(209,968)		(209,968)
Reclassification of loans from HFS to HFI				103,679
Purchases of loans	483,921	333,779	1,053,309	1,459,544
Sale of loans	(269,627)	(232,302)	(888,019)	(866,984)
Purchase of loans for immediate resale	342,467	722,080	1,023,426	5,519,116
Immediate resale of loans	(342,467)	(722,080)	(1,023,426)	(5,519,116)
Repayments received	(40,894)	(43,748)	(149,697)	(128,023)
Changes in fair value recorded in earnings	(20,203)	(16,499)	(54,767)	(68,329)
Other changes	(764)	629	(1,352)	4,606
Fair value, ending balance	632,316	647,178	632,316	647,178
Loans Held-for-Investment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	147,714	18,444	127,611	109,792
Transfer of loans to consolidated securitization	0		0
Reclassification of loans from HFS to HFI				(103,679)
Purchases of loans	32,714	41,402	121,293	55,278
Sale of loans	0	0	0	0
Purchase of loans for immediate resale	0	0	0	0
Immediate resale of loans	0	0	0	0
Repayments received	(24,757)	(2,699)	(68,212)	(3,737)
Changes in fair value recorded in earnings	(13,235)	(4,560)	(40,003)	(5,047)
Other changes	1,057	690	2,804	670
Fair value, ending balance	143,493	53,277	143,493	53,277
Loans Held in Consolidated Securitization
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	0	0	0	0
Transfer of loans to consolidated securitization	209,968		209,968
Reclassification of loans from HFS to HFI				0
Purchases of loans	0	0	0	0
Sale of loans	0	0	0	0
Purchase of loans for immediate resale	0	0	0	0
Immediate resale of loans	0	0	0	0
Repayments received	(12,302)	0	(12,302)	0
Changes in fair value recorded in earnings	(1,139)	0	(1,139)	0
Other changes	0	0	0	0
Fair value, ending balance	$ 196,527	$ 0	$ 196,527	$ 0

Fair Value Measurement - Sche_6

Fair Value Measurement - Schedule of Aggregate Fair Value and Principal Outstanding of All Loans And Loans 90 Days or More Past Due (Details) - USD ($) $ in Thousands		Sep. 30, 2023	Dec. 31, 2022
Financing Receivable, Past Due [Line Items]
Fair value	[1]	$ 972,336	$ 1,010,421
Loans (at fair value)
Financing Receivable, Past Due [Line Items]
Outstanding principal balance		1,002,387	1,047,714
Net fair value and accrued interest adjustments		(30,051)	(37,293)
Fair value		972,336	1,010,421
Loans (at fair value) | Auto Loans
Financing Receivable, Past Due [Line Items]
Fair value		379,500	397,700
Loans > 90 Days Past Due | Loans (at fair value)
Financing Receivable, Past Due [Line Items]
Outstanding principal balance		12,811	9,006
Net fair value and accrued interest adjustments		(10,528)	(7,006)
Fair value		$ 2,283	$ 2,000
[1] Includes $196.5 million as of September 30, 2023 of loans, at fair value, contributed as collateral for the consolidated securitization. Refer to “ Note 6. Fair Value Measurement ” for details.

Fair Value Measurement - Level

Fair Value Measurement - Level Three Assets and Liabilities Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Fair Value, Inputs, Level 3 | Payables to Securitization Note Holders
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	$ 0	$ 0	$ 0	$ 0
Additions	165,318		165,318
Repayments and settlements	(10,016)	0	(10,016)	0
Changes in fair value recorded in earnings	(1,520)	0	(1,520)	0
Fair value, ending balance	153,782	0	153,782	0
Notes receivable and residual certificates (at fair value) | Fair Value, Inputs, Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	3,907	4,698	6,181	8,288
Additions	0		0
Repayments and settlements	(560)	(1,596)	(3,556)	(5,508)
Changes in fair value recorded in earnings	(561)	357	161	679
Fair value, ending balance	2,786	3,459	2,786	3,459
Beneficial Interests
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Changes in fair value recorded in earnings	(7,171)	$ 0	(9,127)	$ 0
Beneficial Interests | Fair Value, Inputs, Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	28,664		0
Additions	14,719		45,254
Changes in fair value recorded in earnings	(6,409)		(8,280)
Fair value, ending balance	$ 36,974		$ 36,974

Fair Value Measurement - Sche_7

Fair Value Measurement - Schedule of Level 3 Fair Value Assumptions for Loan Servicing Assets and Liabilities (Details) - Fair Value, Inputs, Level 3 - Valuation Technique, Discounted Cash Flow	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Minimum
Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items]
Discount rate	13%	13%
Credit risk rate	0.05%	0.03%
Market-servicing rate	0.62%	0.62%
Prepayment rate	2.17%	0.53%
Maximum
Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items]
Discount rate	20%	20%
Credit risk rate	81.10%	91.76%
Market-servicing rate	3.72%	3.72%
Prepayment rate	96.90%	91.99%
Weighted Average
Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items]
Discount rate	16.92%	17.20%
Credit risk rate	15.04%	16.22%
Market-servicing rate	0.63%	0.62%
Prepayment rate	41.57%	41.19%

Fair Value Measurement - Sche_8

Fair Value Measurement - Schedule of Fair Value Sensitivity of Loan Servicing Assets and Liabilities to Adverse Changes in Key Assumptions (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Fair value of loan servicing assets	$ 30,091		$ 36,467
Fair value of loan servicing liabilities	2,393		3,968
Fair Value, Inputs, Level 3
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Fair value of loan servicing assets	30,091		36,467
Fair value of loan servicing liabilities	2,393		3,968
Fair Value, Inputs, Level 3 | Loan Servicing Liabilities
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Fair value of loan servicing liabilities	2,393	$ 2,577	3,968	$ 4,810	$ 6,366	$ 8,780
10% market-servicing rates increase	1,329		2,303
20% market-servicing rates increase	2,702		4,640
Fair Value, Inputs, Level 3 | Loan Servicing Assets
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Fair value of loan servicing assets	30,091	$ 33,339	36,467	$ 37,037	$ 35,171	$ 18,388
10% market-servicing rates increase	(5,689)		(9,989)
20% market-servicing rates increase	$ (16,101)		$ (19,950)

Fair Value Measurement - Sche_9

Fair Value Measurement - Schedule of Servicing Liabilities at Fair Value Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Servicing Asset at Fair Value, Amount [Roll Forward]
Fair value, beginning balance			$ 36,467
Fair value, ending balance	$ 30,091		30,091
Servicing Liability at Fair Value, Amount [Roll Forward]
Fair value, beginning balance			3,968
Fair value, ending balance	2,393		2,393
Fair Value, Inputs, Level 3
Servicing Asset at Fair Value, Amount [Roll Forward]
Fair value, beginning balance			36,467
Fair value, ending balance	30,091		30,091
Servicing Liability at Fair Value, Amount [Roll Forward]
Fair value, beginning balance			3,968
Fair value, ending balance	2,393		2,393
Fair Value, Inputs, Level 3 | Loan Servicing Liabilities
Servicing Liability at Fair Value, Amount [Roll Forward]
Fair value, beginning balance	2,577	$ 6,366	3,968	$ 8,780
Sale of loans	3	9	80	2,296
Changes in fair value recorded in earnings	(187)	(1,565)	(1,655)	(6,266)
Fair value, ending balance	2,393	4,810	2,393	4,810
Fair Value, Inputs, Level 3 | Loan Servicing Assets
Servicing Asset at Fair Value, Amount [Roll Forward]
Fair value, beginning balance	33,339	35,171	36,467	18,388
Sale of loans	3,475	6,048	10,512	26,066
Changes in fair value recorded in earnings	(6,723)	(4,182)	(16,888)	(7,417)
Fair value, ending balance	$ 30,091	$ 37,037	$ 30,091	$ 37,037

Fair Value Measurement - Sch_10

Fair Value Measurement - Schedule Trailing Fee Rollforward (Details) - Fair Value, Inputs, Level 3 - Trailing Fee Liabilities - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	$ 4,265	$ 5,446	$ 4,852	$ 4,315
Issuances	580	618	1,414	3,404
Repayments and settlements	(670)	(816)	(2,096)	(2,211)
Changes in fair value recorded in earnings	(2)	(47)	3	(307)
Fair value, ending balance	$ 4,173	$ 5,201	$ 4,173	$ 5,201

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 67,062		$ 67,062		$ 67,062
Amortization expense	$ 1,100	$ 1,100	$ 3,200	$ 3,200

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Net carrying value	$ 12,413
Developed technology
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	9,400	$ 9,400
Accumulated amortization	(7,833)	(5,483)
Net carrying value	1,567	3,917
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	13,700	13,700
Accumulated amortization	(2,854)	(1,998)
Net carrying value	$ 10,846	$ 11,702

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Schedule of Expected Future Amortization Expense (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Remaining 2023	$ 1,069
2024	1,925
2025	1,142
2026	1,142
2027	1,142
Thereafter	5,993
Net carrying value	$ 12,413

Balance Sheet Components - Sche

Balance Sheet Components - Schedule of Other Assets (Details) - USD ($)	Sep. 30, 2023	Dec. 31, 2022
Other Assets [Abstract]
Servicing fees and other receivables	$ 41,191,000	$ 46,652,000
Loan servicing assets (at fair value)	30,091,000	36,467,000
Prepaid expenses	21,052,000	16,740,000
Intangible assets, net	12,425,000	15,631,000
Interest rate caps	9,796,000	0
Deposits	8,666,000	10,002,000
Notes receivable and residual certificates (at fair value)	2,786,000	6,181,000
Other assets	17,773,000	22,678,000
Total other assets	$ 143,780,000	$ 154,351,000

Balance Sheet Components - Sc_2

Balance Sheet Components - Schedule of Property, Equipment, and Software (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Total property, equipment, and software	$ 77,648	$ 61,327
Accumulated depreciation and amortization	(29,638)	(17,159)
Total property, equipment, and software, net	48,010	44,168
Internally developed software
Property, Plant and Equipment [Line Items]
Total property, equipment, and software	52,808	37,783
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property, equipment, and software	14,050	13,074
Computer and networking equipment
Property, Plant and Equipment [Line Items]
Total property, equipment, and software	6,054	6,049
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property, equipment, and software	$ 4,736	$ 4,421

Balance Sheet Components - Narr

Balance Sheet Components - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Other Assets [Abstract]
Depreciation	$ 3.9	$ 2.7	$ 12.6	$ 6.7
Capitalized internally developed software balances, net of accumulated amortization	32.4		32.4		$ 27.4
Internally developed software impairment	$ 0		$ 2.6

Balance Sheet Components - Sc_3

Balance Sheet Components - Schedule of Accrued Expenses and Other Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Other Assets [Abstract]
Accrued expenses	$ 19,689	$ 23,506
Accrued payroll	21,303	21,825
Loan servicing liabilities (at fair value)	2,393	3,968
Trailing fee liability (at fair value)	4,173	4,852
Other liabilities	4,295	12,795
Total accrued expenses and other liabilities	$ 51,853	$ 66,946

Borrowings - Schedule of aggreg

Borrowings - Schedule of aggregate principal outstanding of all loans (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule of Borrowings [Line Items]
Total payments due	$ 1,012,404	$ 997,702
Unamortized debt discount	(9,012)	(11,308)
Total borrowings	1,003,392	986,394
Warehouse credit facilities | Revolving Credit Facility
Schedule of Borrowings [Line Items]
Total payments due	351,154	336,452
Convertible senior notes
Schedule of Borrowings [Line Items]
Total payments due	$ 661,250	$ 661,250

Borrowings - Narrative (Details

Borrowings - Narrative (Details) $ / shares in Units, shares in Millions, $ in Millions		1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 20, 2021 USD ($) day $ / shares shares	May 31, 2020 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)	Jan. 31, 2023 USD ($)
ULT Warehouse Credit Facility | Revolving Credit Facility
Schedule of Borrowings [Line Items]
Maximum borrowing capacity		$ 175
Redemption price (in percent)		100%
Maximum advance rate (in percent)			72.50%		72.50%		72.50%
ULT Warehouse Credit Facility | Minimum | Revolving Credit Facility
Schedule of Borrowings [Line Items]
Monthly unused fee (in percent)		0.15%
ULT Warehouse Credit Facility | Maximum | Revolving Credit Facility
Schedule of Borrowings [Line Items]
Monthly unused fee (in percent)		1%
UAWT Warehouse Credit Facility | Revolving Credit Facility | Primary Beneficiary
Schedule of Borrowings [Line Items]
Maximum borrowing capacity								$ 200
Maximum advance rate					80%		82.50%
2026 ("Notes")
Schedule of Borrowings [Line Items]
Convertible notes payable			$ 652.2		$ 652.2		$ 649.9
Purchase of capped calls	$ 58.5
Initial conversion price (in dollars per share) | $ / shares	$ 285.26
Initial cap price (in dollars per share) | $ / shares	$ 400.36
Capped call cover (in shares) | shares	2.3
2026 ("Notes") | Fair Value, Inputs, Level 2
Schedule of Borrowings [Line Items]
Fair value of convertible senior notes			428		428		$ 364.8
2026 ("Notes") | Convertible Debt
Schedule of Borrowings [Line Items]
Aggregate principal amount	$ 661.3
Stated interest rate	0.25%
Additional aggregate principal	$ 86.3
Net proceeds from sale of the notes	$ 645.5
Initial conversion rate (in shares)	0.0035056
Initial conversion price (in dollars per share) | $ / shares	$ 285.26
Percent of the principal amount	100%
2026 ("Notes") | Convertible Debt | Conversion Period One
Schedule of Borrowings [Line Items]
Trading days | day	20
Consecutive trading days | day	30
Conversion price maximum threshold	130%
2026 ("Notes") | Convertible Debt | Conversion Period Two
Schedule of Borrowings [Line Items]
Trading days | day	5
Consecutive trading days | day	5
Percentage of the last reported sale price	98%
2026 ("Notes") | Convertible Debt | Conversion Period Three
Schedule of Borrowings [Line Items]
Redemption price (in percent)	100%
Trading days | day	20
Consecutive trading days | day	30
Conversion price maximum threshold	130%
Gross debt issuance cost	$ 15.7
Amortization of debt issuance costs			$ 0.8	$ 0.8	$ 2.3	$ 2.3
Effective interest rate			0.70%		0.70%
Secured Overnight Financing Rate | ULT Warehouse Credit Facility | Minimum | Revolving Credit Facility
Schedule of Borrowings [Line Items]
Basis spread on variable rate		2.75%
Secured Overnight Financing Rate | ULT Warehouse Credit Facility | Maximum | Revolving Credit Facility
Schedule of Borrowings [Line Items]
Basis spread on variable rate		4.13%
UAWT Benchmark Rate | UAWT Warehouse Credit Facility | Minimum | Revolving Credit Facility | Primary Beneficiary
Schedule of Borrowings [Line Items]
Basis spread on variable rate					3%
UAWT Benchmark Rate | UAWT Warehouse Credit Facility | Maximum | Revolving Credit Facility | Primary Beneficiary
Schedule of Borrowings [Line Items]
Basis spread on variable rate					4%

Borrowings - Schedule of Assets

Borrowings - Schedule of Assets Pledged as Collateral (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule of Borrowings [Line Items]
Outstanding borrowings	$ 1,012,404	$ 997,702
Aggregate fair value of loans purchased and held by ULT/UAWT	972,336	1,010,421
Restricted cash pledged as collateral	98,447	110,056
Variable Interest Entity, Primary Beneficiary
Schedule of Borrowings [Line Items]
Restricted cash pledged as collateral	23,888	13,147
ULT Warehouse Credit Facility | Revolving Credit Facility | Variable Interest Entity, Primary Beneficiary
Schedule of Borrowings [Line Items]
Outstanding borrowings	170,303	163,773
ULT Warehouse Credit Facility | Revolving Credit Facility | Variable Interest Entity, Primary Beneficiary | Asset Pledged as Collateral
Schedule of Borrowings [Line Items]
Aggregate outstanding principal of loans pledged as collateral	236,822	228,895
Aggregate fair value of loans purchased and held by ULT/UAWT	241,049	256,024
Restricted cash pledged as collateral	5,067	8,547
UAWT Warehouse Credit Facility | Revolving Credit Facility | Variable Interest Entity, Primary Beneficiary
Schedule of Borrowings [Line Items]
Outstanding borrowings	180,851	172,679
Aggregate outstanding principal of loans pledged as collateral	308,338	221,847
Aggregate fair value of loans purchased and held by ULT/UAWT	296,694	216,539
Restricted cash pledged as collateral	$ 360	$ 843

Borrowings - Schedule of Maturi

Borrowings - Schedule of Maturities of All Borrowings (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Disclosure [Abstract]
Remaining 2023	$ 0
2024	0
2025	180,851
2026	831,553
2027	0
Thereafter	0
Total	$ 1,012,404	$ 997,702

Stockholders_ Equity - Schedule

Stockholders’ Equity - Schedule of Reserved Shares of Common Stock for Issuance (Details) - shares	Sep. 30, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Shares reserved of common stock for issuance (in shares)	28,773,991	27,666,452
Shares available for future issuance under 2020 plan | Common stock
Class of Stock [Line Items]
Shares reserved of common stock for issuance (in shares)	6,471,704	5,842,057
Options issued and outstanding
Class of Stock [Line Items]
Shares reserved of common stock for issuance (in shares)	13,014,493	12,547,010
Restricted stock units outstanding
Class of Stock [Line Items]
Shares reserved of common stock for issuance (in shares)	6,391,568	6,046,796
Performance-based restricted stock unit outstanding
Class of Stock [Line Items]
Shares reserved of common stock for issuance (in shares)	0	687,500
Shares available for issuance under employee stock purchase plan
Class of Stock [Line Items]
Shares reserved of common stock for issuance (in shares)	2,896,226	2,543,089

Stockholders_ Equity - Narrativ

Stockholders’ Equity - Narrative (Details)			3 Months Ended		9 Months Ended
	Feb. 24, 2023 shares	Apr. 08, 2021 USD ($) shares	Sep. 30, 2023 USD ($) $ / shares shares	Sep. 30, 2022 USD ($) shares	Sep. 30, 2023 USD ($) vesting_tranche $ / shares shares	Sep. 30, 2022 USD ($) $ / shares shares	Dec. 31, 2022 $ / shares shares	Feb. 28, 2022 USD ($)	Dec. 31, 2020 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, authorized (in shares) | shares			700,000,000		700,000,000		700,000,000		700,000,000
Common stock, par value (in dollars per share) | $ / shares			$ 0.0001		$ 0.0001		$ 0.0001		$ 0.0001
Authorized share repurchase amount								$ 400,000,000
Stock repurchase program, remaining authorized repurchase amount (in dollars per share)			$ 222,100,000		$ 222,100,000
Aggregate intrinsic value of options exercised					18,500,000	$ 151,700,000
Fair value of options vested during period					$ 26,400,000	17,300,000
Issuance of common stock upon settlement of restricted stock units				$ (8,000)		$ (8,000)
Annual target bonus opportunity percentage					75%
Number of vesting tranches | vesting_tranche					9
Dividend yield					0%
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common stock under employee stock purchase plan (in shares) | shares			147,325	114,902	459,459	162,796
Weighted Average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share) | $ / shares					$ 8.06	$ 23.29
Options issued and outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense related to unvested stock options			$ 47,500,000		$ 47,500,000
Dividend yield			0%	0%	0%	0%
Options issued and outstanding | Weighted Average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of recognition					2 years 8 months 12 days
Restricted stock units outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense related to unvested stock options			$ 174,000,000		$ 174,000,000
Unvested (in dollars per share) | $ / shares			$ 34.65		$ 34.65		51.28
Restricted stock units outstanding | Weighted Average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of recognition					2 years 2 months 12 days
Restricted stock units outstanding | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					1 year
Restricted stock units outstanding | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					4 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		2 years
Unvested (in dollars per share) | $ / shares			$ 0		$ 0		$ 123.33
Unrecognized stock-based compensation expense			$ 0		$ 0
Restricted Stock | Prodigy Software, Inc.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock issued (in shares) | shares		82,201
Issuance of common stock upon settlement of restricted stock units		$ 10,100,000
Performance-based restricted stock unit outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for settlement of cancelled awards (in shares) | shares	687,500
Unvested (in dollars per share) | $ / shares			$ 68.76		$ 68.76
Unrecognized stock-based compensation expense			$ 39,000,000		$ 39,000,000
Dividend yield					0%
Shares available for issuance under employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of recognition					4 months 24 days
Unrecognized stock-based compensation expense			$ 2,400,000		$ 2,400,000
Purchase period					6 months
ESPP purchase price of common stock, percent of market price					85%
Dividend yield			0%	0%	0%	0%

Stockholders_ Equity - Schedu_2

Stockholders’ Equity - Schedule of Stock Option Activity (Details) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares
Number of Options
Beginning balance (in shares) | shares	12,547,010
Options granted (in shares) | shares	2,088,207
Options exercised (in shares) | shares	(1,058,804)
Options cancelled and forfeited (in shares) | shares	(561,920)
Ending balance (in shares) | shares	13,014,493	12,547,010
Options exercisable (in shares) | shares	8,621,628
Options vested and expected to vest (in shares) | shares	13,014,493
Weighted-Average Exercise Price Per Share
Options outstanding (in dollars per share) | $ / shares	$ 14.65
Options granted (in dollars per share) | $ / shares	15.37
Options exercised (in dollars per share) | $ / shares	8.95
Options cancelled and forfeited (in dollars per share) | $ / shares	31.78
Options outstanding (in dollars per share) | $ / shares	14.49	$ 14.65
Options exercisable, weighted average exercise price per share (in dollars per share) | $ / shares	8.71
Options vested and expected to vest, weighted average exercise price per share (in dollars per share) | $ / shares	$ 14.49
Weighted-Average Remaining Contractual Life (years)
Options outstanding	6 years 3 months 18 days	6 years 7 months 6 days
Options exercisable	5 years
Options vested and expected to vest	6 years 3 months 18 days
Aggregate Intrinsic Value
Balances aggregate intrinsic value | $	$ 235,725	$ 77,289
Options exercisable | $	188,958
Options vested and expected to vest | $	$ 235,725

Stockholders_ Equity - Schedu_3

Stockholders’ Equity - Schedule of RSU Activity (Details) - Restricted stock units outstanding	9 Months Ended
	Sep. 30, 2023 $ / shares shares
Number of Shares
Beginning balance (in shares) | shares	6,046,796
RSUs granted (in shares) | shares	3,765,967
RSUs vested (in shares) | shares	(2,247,325)
RSUs cancelled and forfeited (in shares) | shares	(1,173,870)
Ending balance (in shares) | shares	6,391,568
Weighted-Average Grant Date Fair Value Per Share
Beginning balance (in dollars per share) | $ / shares	$ 51.28
RSUs granted (in dollars per share) | $ / shares	18.70
RSUs vested (in dollars per share) | $ / shares	37.67
RSUs cancelled and forfeited (in dollars per share) | $ / shares	63.39
Ending balance (in dollars per share) | $ / shares	$ 34.65

Stockholders_ Equity - Schedu_4

Stockholders’ Equity - Schedule of Restricted Stock Activity (Details) - Restricted Stock	9 Months Ended
	Sep. 30, 2023 $ / shares shares
Number of Shares
Beginning balance (in shares) | shares	10,271
RSUs vested (in shares) | shares	(10,271)
Ending balance (in shares) | shares	0
Weighted-Average Grant Date Fair Value Per Share
Beginning balance (in dollars per share) | $ / shares	$ 123.33
Vested (in dollars per share) | $ / shares	123.33
Ending balance (in dollars per share) | $ / shares	$ 0

Stockholders_ Equity - Schedu_5

Stockholders’ Equity - Schedule of Weighted-Average Assumptions (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility, maximum				179.35%
Risk free rate, maximum				3.13%
Dividend yield			0%
Options issued and outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility, minimum	53.33%	49.66%	50.96%	47.58%
Expected volatility, maximum	53.38%	50.73%	53.38%	50.73%
Risk free rate, minimum	4.23%	3.28%	3.45%	1.70%
Risk free rate, maximum	4.60%	4.02%	4.60%	4.02%
Dividend yield	0%	0%	0%	0%
Options issued and outstanding | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years 3 months 18 days	5 years 1 month 6 days	5 years 2 months 12 days	5 years 1 month 6 days
Options issued and outstanding | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		6 years 1 month 6 days	7 years	7 years
Performance-based restricted stock unit outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)			6 years 10 months 24 days
Expected volatility			48.43%
Risk-free interest rate			1.89%
Dividend yield			0%
Shares available for issuance under employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 months	6 months	6 months	6 months
Expected volatility, minimum			97.74%	91.98%
Expected volatility	131.05%	179.35%
Expected volatility, maximum			131.05%
Risk free rate, minimum			4.97%	0.72%
Risk-free interest rate	5.55%	3.13%
Risk free rate, maximum			5.55%
Dividend yield	0%	0%	0%	0%

Stockholders_ Equity - Schedu_6

Stockholders’ Equity - Schedule of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 35,568	$ 36,656	$ 142,273	$ 92,035
Sales and marketing
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	3,231	3,028	5,097	7,890
Customer operations
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	2,768	2,682	8,744	6,386
Engineering and product development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	17,357	21,726	92,725	53,254
General, administrative, and other
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 12,212	$ 9,220	$ 35,707	$ 24,505

Leases - Narrative (Details)

Leases - Narrative (Details) $ in Millions	Sep. 30, 2023 USD ($)
Leases [Abstract]
Letter of credit outstanding	$ 3.4

Leases - Schedule of Future Min

Leases - Schedule of Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Leases [Abstract]
Remaining 2023	$ 3,828
2024	17,054
2025	17,544
2026	18,055
2027	17,745
Thereafter	34,815
Total undiscounted lease payments	109,041
Less: Tenant improvement receivables	(2,337)
Less: Present value adjustment	(13,350)
Operating lease liabilities	$ 93,354	$ 100,787

Leases - Schedule of Operating

Leases - Schedule of Operating Lease Expense and Supplemental Cash and Non-cash Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Leases [Abstract]
Rent expense	$ 4,016	$ 3,961	$ 12,062	$ 11,837
Variable lease payments	1,016	936	2,936	2,724
Cash paid for amounts included in the measurement of lease liabilities	$ 3,803	$ 3,197	$ 11,263	$ 7,967
Weighted-average remaining lease term (in years)	6 years 7 months 28 days		6 years 7 months 28 days
Weighted-average discount rate	3.86%		3.86%

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	1 Months Ended	9 Months Ended
	Jun. 22, 2022 lawsuit	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Loss Contingencies [Line Items]
Loss contingency, new claims filed, number | lawsuit	2
Obligation to Repurchase Loans
Loss Contingencies [Line Items]
Loss contingency, ownership loan facilitated term		3 days
Loan purchase obligation		$ 40.2	$ 17.8
Maximum estimate of potential loss		$ 13,040.8	$ 15,551.1

Income Taxes - Schedule of Effe

Income Taxes - Schedule of Effective Tax Rates (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 10	$ 12	$ 44	$ 55
Effective tax rate	(0.03%)	(0.02%)	(0.02%)	(0.10%)

Net Loss Per Share - Schedule o

Net Loss Per Share - Schedule of Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Numerator:
Net loss	$ (40,315)	$ (56,223)	$ (197,734)	$ (53,402)
Denominator:
Weighted-average common shares outstanding used to calculate net loss per share, basic (in shares)	84,404,966	81,672,099	83,158,146	83,236,131
Weighted-average common shares outstanding used to calculate net loss per share, diluted (in shares)	84,404,966	81,672,099	83,158,146	83,236,131
Net loss per share, basic (in dollars per share)	$ (0.48)	$ (0.69)	$ (2.38)	$ (0.64)
Net loss per share, diluted (in dollars per share)	$ (0.48)	$ (0.69)	$ (2.38)	$ (0.64)

Net Loss Per Share - Schedule_2

Net Loss Per Share - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	21,915,816	19,517,922	21,915,816	19,517,922
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	13,014,493	11,723,427	13,014,493	11,723,427
Unvested RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	6,391,568	4,679,719	6,391,568	4,679,719
Unvested PRSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	0	687,500	0	687,500
Purchase rights committed under the ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	191,677	109,198	191,677	109,198
Convertible debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	2,318,078	2,318,078	2,318,078	2,318,078

Reorganization Expenses (Detail

Reorganization Expenses (Details) - January 2023 Plan		3 Months Ended	9 Months Ended
	Jan. 31, 2023 employee	Sep. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)
Restructuring Cost and Reserve [Line Items]
Reorganization expenses		$ 0
One-time non-cash savings amount			$ 2,900,000
Employee Severance
Restructuring Cost and Reserve [Line Items]
Expected reduction in workforce, percent	20%
Expected reduction in workforce, number of employees | employee	365
Reorganization expenses			15,500,000
Impairment of Intangible Assets
Restructuring Cost and Reserve [Line Items]
Reorganization expenses			$ 2,600,000