Post (POST) 10-Q 2 Aug 24 2024 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Jun. 30, 2024	Jul. 29, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2024
Document Transition Report	false
Entity File Number	1-35305
Entity Registrant Name	Post Holdings, Inc.
Entity Incorporation, State or Country Code	MO
Entity Tax Identification Number	45-3355106
Entity Address, Address Line One	2503 S. Hanley Road
Entity Address, City or Town	St. Louis
Entity Address, State or Province	MO
Entity Address, Postal Zip Code	63144
City Area Code	314
Local Phone Number	644-7600
Title of 12(b) Security	Common Stock, $0.01 par value per share
Trading Symbol	POST
Security Exchange Name	NYSE
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 (in shares)		58,427,526
Entity Central Index Key	0001530950
Current Fiscal Year End Date	--09-30
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Amendment Flag	false

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
Net Sales	$ 1,947.7	$ 1,859.4	$ 5,912.6	$ 5,045.6
Cost of goods sold	1,370.4	1,357.8	4,183.1	3,715.3
Gross Profit	577.3	501.6	1,729.5	1,330.3
Selling, general and administrative expenses	324.5	300.9	988.7	768.9
Amortization of intangible assets	46.4	42.4	138.5	115.4
Other operating expense (income), net	3.2	0	(0.3)	0.1
Operating Profit	203.2	158.3	602.6	445.9
Interest expense, net	78.8	72.7	236.9	202.4
Gain on extinguishment of debt, net	(1.8)	(6.4)	(4.6)	(21.2)
(Income) expense on swaps, net	(3.1)	(17.1)	4.7	(20.4)
Other income, net	(2.3)	(16)	(8.6)	(32.9)
Earnings before Income Taxes and Equity Method Loss	131.6	125.1	374.2	318
Income tax expense	31.7	26.8	88.8	70.4
Equity method loss, net of tax	0	0	0.1	0.2
Net Earnings Including Noncontrolling Interests	99.9	98.3	285.3	247.4
Less: Net earnings attributable to noncontrolling interests	0.1	8.7	0.2	11.8
Net Earnings	$ 99.8	$ 89.6	$ 285.1	$ 235.6
Earnings Per Share [Abstract]
Earnings, Per Basic Share	$ 1.66	$ 1.49	$ 4.72	$ 4.13
Earnings, Per Diluted Share	$ 1.53	$ 1.38	$ 4.36	$ 3.82
Weighted Average Number of Shares Outstanding
Weighted-Average Common Shares Outstanding, Basic (in shares)	60	61.6	60.4	59.7
Weighted-Average Common Shares Outstanding, Diluted (in shares)	67	68.5	67.3	66.7

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Statement of Comprehensive Income [Abstract]
Net Earnings Including Noncontrolling Interests	$ 99.9	$ 98.3	$ 285.3	$ 247.4
Pension and postretirement benefits adjustments:
Unrealized pension and other postretirement benefit obligations	0	0	(8.3)	0
Reclassifications to net earnings	(0.2)	(1.2)	(0.8)	(3.5)
Foreign currency translation adjustments:
Unrealized foreign currency translation adjustments	2.6	36.1	56.1	185.3
Tax benefit (expense) on pension and postretirement benefits adjustments:
Unrealized pension and other postretirement benefit obligations	0	0	2	0
Reclassifications to net earnings	0.1	0.2	0.3	0.8
Total Other Comprehensive Income Including Noncontrolling Interests	2.5	35.1	49.3	182.6
Less: Comprehensive income attributable to noncontrolling interests	0.3	8.2	1.5	10.2
Total Comprehensive Income	$ 102.1	$ 125.2	$ 333.1	$ 419.8

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2024	Sep. 30, 2023
ASSETS
Cash and cash equivalents	$ 333.8	$ 93.3
Restricted cash	10	23.9
Receivables, net	536.1	512.4
Inventories	795	789.9
Prepaid expenses and other current assets	81.3	59
Total Current Assets	1,756.2	1,478.5
Property, net	2,187.7	2,021.4
Goodwill	4,648.7	4,574.4
Other intangible assets, net	3,169	3,212.4
Other assets	366.9	360
Total Assets	12,128.5	11,646.7
LIABILITIES AND SHAREHOLDERS’ EQUITY
Current portion of long-term debt	1.2	1.1
Accounts payable	392.6	368.8
Other current liabilities	463.4	435.4
Total Current Liabilities	857.2	805.3
Long-term debt	6,397.8	6,039
Deferred income taxes	645.9	674.4
Other liabilities	271.8	276.7
Total Liabilities	8,172.7	7,795.4
Common stock	0.9	0.9
Additional paid-in capital	5,312.5	5,288.1
Retained earnings	1,701.6	1,416.5
Accumulated other comprehensive loss	(87.1)	(135.1)
Treasury stock, at cost	(2,982.8)	(2,728.3)
Total Shareholders’ Equity Excluding Noncontrolling Interests	3,945.1	3,842.1
Noncontrolling interests	10.7	9.2
Total Shareholders’ Equity	3,955.8	3,851.3
Total Liabilities and Shareholders’ Equity	$ 12,128.5	$ 11,646.7

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Cash Flows from Operating Activities:
Net Earnings Including Noncontrolling Interests	$ 285.3	$ 247.4
Adjustments to reconcile net earnings including noncontrolling interests to net cash provided by operating activities:
Depreciation and amortization	352.7	293.3
Unrealized loss (gain) on interest rate swaps, foreign exchange contracts and warrant liability, net	15.9	(27.4)
Gain on extinguishment of debt, net	(4.6)	(21.2)
Non-cash stock-based compensation expense	60.9	57.2
Equity method loss, net of tax	0.1	0.2
Deferred income taxes	(33.9)	(11.2)
Non-cash gain on write-off of deferred underwriting commissions	0	(10.7)
Other, net	0.9	(4.3)
Other changes in operating assets and liabilities, net of business acquisitions:
Decrease (increase) in receivables, net	23.7	(17.7)
Decrease (increase) in inventories	20.1	(20.7)
(Increase) decrease in prepaid expenses and other current assets	(28.2)	40.5
Decrease (increase) in other assets	1.4	(15)
Decrease in accounts payable and other current liabilities	(13.9)	(38.1)
Increase in non-current liabilities	15.9	8.2
Net Cash Provided by Operating Activities	696.3	480.5
Cash Flows from Investing Activities:
Business acquisitions, net of cash acquired	(248.1)	(715.2)
Return of subsidiary investments held in trust account	0	345
Additions to property	(290.3)	(201.9)
Other, net	0.1	4.2
Net Cash Used in Investing Activities	(538.3)	(567.9)
Cash Flows from Financing Activities:
Proceeds from issuance of debt	1,645	530
Repayments of debt, net of discounts	(1,266.6)	(178.4)
Purchases of treasury stock	(248.7)	(242.4)
Payments of debt issuance costs and deferred financing fees	(19.9)	(3.1)
Payments of debt premiums	(4.4)	0
Payment for share repurchase contracts	(50)	0
Proceeds from share repurchase contracts	50.9	0
Redemption of Post Holdings Partnering Corporation Series A common stock	0	(312.5)
Financing portion of cash paid for rate-lock interest rate swaps	0	(43.5)
Other, net	(39.6)	(29.8)
Net Cash Provided by (Used in) Financing Activities	66.7	(279.7)
Effect of Exchange Rate Changes on Cash, Cash Equivalents and Restricted Cash	1.9	3.8
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	226.6	(363.3)
Cash, Cash Equivalents and Restricted Cash, Beginning of Year	117.2	590.1
Cash, Cash Equivalents and Restricted Cash, End of Period	$ 343.8	$ 226.8

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Shareholders' Equity Statement - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Retirement Benefit Adjustments, net of tax	Hedging Adjustments, net of tax	Foreign Currency Translation Adjustments	Treasury Stock	Noncontrolling Interests
Shareholders' Equity Excluding Noncontrolling Interest, Beginning of period at Sep. 30, 2022		$ 0.9	$ 4,748.2	$ 1,109	$ (29.7)	$ 74.8	$ (308)	$ (2,341.2)
Total Shareholders' Equity, Beginning of period at Sep. 30, 2022									$ 11.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activity under stock and deferred compensation plans			(29)
Non-cash stock-based compensation expense			57.2
Payment for share repurchase contracts	$ 0
Proceeds from share repurchase contracts	0		0
Issuance of common stock			492.3
Net Earnings	235.6			235.6
Post Holdings Partnering Corporation deemed dividend				6.2
Net change in retirement benefits, net of tax					(2.7)
Foreign currency translation adjustments							186.9		(1.6)
Purchases of treasury stock								(250.5)
Net earnings attributable to noncontrolling interests	11.8								(0.3)
Shareholders' Equity Excluding Noncontrolling Interest, End of period at Jun. 30, 2023	3,950	0.9	5,268.7	1,350.8	(32.4)	74.8	(121.1)	(2,591.7)
Total Shareholders' Equity, End of period at Jun. 30, 2023	3,959.8								9.8
Shareholders' Equity Excluding Noncontrolling Interest, Beginning of period at Mar. 31, 2023		0.9	4,757.5	1,253.8	(31.4)	74.8	(157.7)	(2,424.9)
Total Shareholders' Equity, Beginning of period at Mar. 31, 2023									10.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activity under stock and deferred compensation plans			(1.1)
Non-cash stock-based compensation expense			20
Proceeds from share repurchase contracts			0
Issuance of common stock			492.3
Net Earnings	89.6			89.6
Post Holdings Partnering Corporation deemed dividend				7.4
Net change in retirement benefits, net of tax					(1)
Foreign currency translation adjustments							36.6		(0.5)
Purchases of treasury stock								(166.8)
Net earnings attributable to noncontrolling interests	8.7								(0.6)
Shareholders' Equity Excluding Noncontrolling Interest, End of period at Jun. 30, 2023	3,950	0.9	5,268.7	1,350.8	(32.4)	74.8	(121.1)	(2,591.7)
Total Shareholders' Equity, End of period at Jun. 30, 2023	3,959.8								9.8
Shareholders' Equity Excluding Noncontrolling Interest, Beginning of period at Sep. 30, 2023	3,842.1	0.9	5,288.1	1,416.5	(30.3)	74.8	(179.6)	(2,728.3)
Total Shareholders' Equity, Beginning of period at Sep. 30, 2023	3,851.3								9.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activity under stock and deferred compensation plans			(37.4)
Non-cash stock-based compensation expense			60.9
Payment for share repurchase contracts	(50)		(50)
Proceeds from share repurchase contracts	50.9		50.9
Issuance of common stock			0
Net Earnings	285.1			285.1
Post Holdings Partnering Corporation deemed dividend				0
Net change in retirement benefits, net of tax					(6.8)
Foreign currency translation adjustments							54.8		1.3
Purchases of treasury stock								(254.5)
Net earnings attributable to noncontrolling interests	0.2								0.2
Shareholders' Equity Excluding Noncontrolling Interest, End of period at Jun. 30, 2024	3,945.1	0.9	5,312.5	1,701.6	(37.1)	74.8	(124.8)	(2,982.8)
Total Shareholders' Equity, End of period at Jun. 30, 2024	3,955.8								10.7
Shareholders' Equity Excluding Noncontrolling Interest, Beginning of period at Mar. 31, 2024		0.9	5,240.1	1,601.8	(37)	74.8	(127.2)	(2,773.1)
Total Shareholders' Equity, Beginning of period at Mar. 31, 2024									10.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activity under stock and deferred compensation plans			0.4
Non-cash stock-based compensation expense			21.1
Payment for share repurchase contracts			0
Proceeds from share repurchase contracts			50.9
Issuance of common stock			0
Net Earnings	99.8			99.8
Post Holdings Partnering Corporation deemed dividend				0
Net change in retirement benefits, net of tax					(0.1)
Foreign currency translation adjustments							2.4		0.2
Purchases of treasury stock								(209.7)
Net earnings attributable to noncontrolling interests	0.1								0.1
Shareholders' Equity Excluding Noncontrolling Interest, End of period at Jun. 30, 2024	3,945.1	$ 0.9	$ 5,312.5	$ 1,701.6	$ (37.1)	$ 74.8	$ (124.8)	$ (2,982.8)
Total Shareholders' Equity, End of period at Jun. 30, 2024	$ 3,955.8								$ 10.7

Basis of Presentation

Basis of Presentation	9 Months Ended
	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	BASIS OF PRESENTATION These unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”), under the rules and regulations of the United States (the “U.S.”) Securities and Exchange Commission (the “SEC”). These unaudited condensed consolidated financial statements have been prepared on a basis substantially consistent with, and should be read in conjunction with, the audited consolidated financial statements of Post Holdings, Inc. (herein referred to as “Post,” the “Company,” “us,” “our” or “we,” and unless otherwise stated or context otherwise indicates, all such references herein mean Post Holdings, Inc. and its subsidiaries), which are included in the Company’s Annual Report on Form 10-K for the fiscal year ended September 30, 2023, filed with the SEC on November 17, 2023. These unaudited condensed consolidated financial statements include all adjustments (consisting of normal recurring adjustments and accruals) that management considers necessary for a fair statement of the Company’s results of operations, comprehensive income, financial condition, cash flows and shareholders’ equity for the interim periods presented. Interim results are not necessarily indicative of the results for any other interim period or for the entire fiscal year. Certain reclassifications have been made to previously reported financial information to conform to the current period presentation.

Recently Issued and Adopted Acc

Recently Issued and Adopted Accounting Standards (Notes)	9 Months Ended
	Jun. 30, 2024
Accounting Standards Update and Change in Accounting Principle [Abstract]
Recently Issued and Adopted Accounting Standards	RECENTLY ISSUED ACCOUNTING STANDARDS The Company has considered all new accounting pronouncements and has concluded there are no new pronouncements (other than the ones described below) that had or will have a material impact on the Company’s results of operations, comprehensive income, financial position, cash flows, shareholders’ equity or related disclosures based on current information. In December 2023, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) 2023-09, “Income Taxes (Topic 740): Improvements to Income Tax Disclosures.” This ASU is effective for fiscal years beginning after December 15, 2024 (i.e., the Company’s annual financial statements for the year ended September 30, 2026), with early adoption permitted. This ASU should be adopted prospectively; however, retrospective adoption is permitted. The Company is currently evaluating the impact of this standard. In November 2023, the FASB issued ASU 2023-07, “Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures.” This ASU is effective for fiscal years beginning after December 15, 2023 (i.e., the Company’s annual financial statements for the year ended September 30, 2025) and for interim periods within fiscal years beginning after December 15, 2024 (i.e., the Company’s interim financial statements for the three months ended December 31, 2025), with early adoption permitted. This ASU requires retrospective adoption. The Company is currently evaluating the impact of this standard.

Noncontrolling Interests, Equit

Noncontrolling Interests, Equity Interests and Related Party Transactions (Notes)	9 Months Ended
	Jun. 30, 2024
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments and Joint Ventures Disclosure - 8th Ave	8th Avenue The Company has a 60.5% common equity interest in 8th Avenue Food & Provisions, Inc. (“8th Avenue”) that is accounted for using the equity method. In determining the accounting treatment of the common equity interest, management concluded that 8th Avenue was not a variable interest entity as defined by Accounting Standards Codification (“ASC”) Topic 810, “Consolidation,” and as such, 8th Avenue was evaluated under the voting interest model. Based on the terms of 8th Avenue’s governing documents, management determined that the Company does not have a controlling voting interest in 8th Avenue due to substantive participating rights held by third parties associated with the governance of 8th Avenue. However, Post does retain significant influence, and therefore, the use of the equity method of accounting is required. During fiscal 2022, 8th Avenue’s equity method loss attributable to Post exceeded the Company’s remaining investment in 8th Avenue. As such, in accordance with ASC Topic 323, “Investments—Equity Method and Joint Ventures,” the Company discontinued applying the equity method to the investment after reducing the balance of the investment to zero. The Company’s investment in 8th Avenue was zero at both June 30, 2024 and September 30, 2023, and the Company did not recognize an equity method gain (loss) attributable to 8th Avenue for the three or nine months ended June 30, 2024 or 2023. During the three and nine months ended June 30, 2024, the Company had net sales to 8th Avenue of $1.5 and $5.3, respectively, and purchases from and royalties paid to 8th Avenue of $21.5 and $61.1, respectively. During the three and nine months ended June 30, 2023, the Company had net sales to 8th Avenue of $1.2 and $6.7, respectively, and purchases from and royalties paid to 8th Avenue of $16.8 and $65.2, respectively. Sales and purchases between the Company and 8th Avenue were all made at arm’s-length. The Company had current payables with 8th Avenue of $15.6 and $13.3 at June 30, 2024 and September 30, 2023, respectively, which were included in “Accounts payable” on the Condensed Consolidated Balance Sheets and primarily related to related party purchases and royalties. Current receivables with 8th Avenue at June 30, 2024 and September 30, 2023 were immaterial. In addition, the Company had a long-term receivable and a long-term liability with 8th Avenue of $12.9 and $0.7, respectively, at both June 30, 2024 and September 30, 2023, which were included in “Other assets” and “Other liabilities,” respectively, on the Condensed Consolidated Balance Sheets and related to tax indemnifications.
Equity Method Investments and Joint Ventures Disclosure - WBX	Weetabix East Africa and Alpen The Company holds a controlling equity interest in Weetabix East Africa Limited (“Weetabix East Africa”). Weetabix East Africa is a Kenyan-based company that produces ready-to-eat (“RTE”) cereal and muesli. The Company owns 50.1% of Weetabix East Africa and holds a controlling voting and financial interest through its appointment of management and representation on Weetabix East Africa’s board of directors. Accordingly, Weetabix East Africa is fully consolidated into the Company’s financial statements and its assets and results of operations are reported in the Weetabix segment. The remaining interest in the consolidated net earnings and net assets of Weetabix East Africa is allocated to NCI. The Company holds an equity interest in Alpen Food Company South Africa (Pty) Limited (“Alpen”). Alpen is a South African-based company that produces RTE cereal and muesli. The Company owns 50.0% of Alpen’s common stock with no other indicators of control, and accordingly, the Company accounts for its investment in Alpen using the equity method. The investment in Alpen was $3.7 and $3.6 at June 30, 2024 and September 30, 2023, respectively, and was included in “Other assets” on the Condensed Consolidated Balance Sheets.
Equity Method Investments and Joint Ventures Disclosure - BRBR	BellRing Transactions between the Company and BellRing Brands, Inc. (“BellRing”) are considered related party transactions as certain of the Company’s officers and/or directors serve as officers and/or directors of BellRing. On September 30, 2022, Comet Processing, Inc. (“Comet”), a wholly-owned subsidiary of the Company, entered into a co-packing agreement with Premier Nutrition Company, LLC (“Premier Nutrition”), a subsidiary of BellRing (the “Co-Packing Agreement”). Under the Co-Packing Agreement, Premier Nutrition procures certain packaging materials for Comet that Comet utilizes in the production of ready-to-drink (“RTD”) shakes for Premier Nutrition. In December 2023, in accordance with the terms of the Co-Packing Agreement, Comet began manufacturing RTD shakes for Premier Nutrition. Sales of RTD shakes to Premier Nutrition during the three and nine months ended June 30, 2024 were immaterial and there were no sales of RTD shakes to Premier Nutrition during fiscal 2023. Other related party transactions and balances between the Company and BellRing were immaterial as of and for the three and nine months ended June 30, 2024 and 2023.
Noncontrolling Interests, Equity Interests and Related Party Transactions - PHPC	Post Holdings Partnering Corporation In May and June 2021, the Company and Post Holdings Partnering Corporation (“PHPC”), a special purpose acquisition company, consummated the initial public offering of 34.5 units of PHPC (the “PHPC Units” and such transaction, the “PHPC IPO”), of which a wholly-owned subsidiary of the Company (“PHPC Sponsor”) purchased 4.0 PHPC Units. Each PHPC Unit consisted of one share of Series A common stock of PHPC (“PHPC Series A Common Stock”) and one-third of one redeemable warrant to purchase one share of PHPC Series A Common Stock at an exercise price of $11.50 per share (the “PHPC Warrants”). The PHPC Units were sold at a price of $10.00 per PHPC Unit, generating gross proceeds to PHPC of $345.0. Under the terms of the PHPC IPO, PHPC was required to consummate a partnering transaction by May 28, 2023, which could have been extended to August 28, 2023 in certain circumstances (the “Combination Period”). Substantially concurrently with the closing of the PHPC IPO, PHPC completed the private sale of 1.1 units of PHPC (the “PHPC Private Placement Units”), at a purchase price of $10.00 per PHPC Private Placement Unit, to PHPC Sponsor, generating proceeds to PHPC of $10.9 (the “PHPC Private Placement”). Each PHPC Private Placement Unit consisted of one share of PHPC Series A Common Stock and one-third of one redeemable warrant of PHPC to purchase one share of PHPC Series A Common Stock at an exercise price of $11.50 per share (the “PHPC Private Placement Warrants”). In addition, the Company, through PHPC Sponsor’s ownership of 8.6 shares of Series F common stock of PHPC (the “PHPC Series F Common Stock”), had certain governance rights in PHPC relating to the election of PHPC directors and voting rights on amendments to PHPC’s amended and restated certificate of incorporation. PHPC Sponsor was the primary beneficiary of PHPC as it had, through its equity interest, the right to receive benefits or the obligation to absorb losses from PHPC, as well as the power to direct a majority of the activities that significantly impacted PHPC’s economic performance, including partnering transaction target identification. As such, PHPC was fully consolidated into the Company’s financial statements until the time of its dissolution, as discussed below. Pr oceeds of $345.0 were deposited in a trust account established for the benefit of PHPC’s public stockholders, which consisted of certain proceeds from the PHPC IPO and certain proceeds from the PHPC Private Placement, net of underwriters’ discounts and commissions and other costs and expenses. The public stockholders’ ownership of PHPC equity represented a noncontrolling interest (“NCI”) to the Company, which was classified outside of permanent shareholders’ equity as the PHPC Series A Common Stock was redeemable at the option of the public stockholders in certain circumstances. The carrying amount of the redeemable NCI was equal to the greater of (i) the initial carrying amount, increased or decreased for the redeemable NCI’s share of PHPC’s net earnings or loss, other comprehensive income or loss (“OCI”) and distributions or (ii) the redemption value. The redemption value represented the amount the public stockholders of PHPC Series A Common Stock would be entitled in certain circumstances to redeem their shares of PHPC Series A Common Stock for, which was a pro-rata portion of the amount in the trust account at $10.00 per share of PHPC Series A Common Stock held, plus any pro-rata interest earned on the funds held in the trust account (which interest was net of taxes payable, and less up to $0.1 of interest to pay dissolution expenses). Remeasurements to the redemption value of the redeemable NCI were recognized as a deemed dividend and recorded to retained earnings on the balance sheet prior to the PHPC Redemption (as defined below). In connection with the PHPC IPO, PHPC incurred offering costs of $17.9, of which $10.7 were deferred underwriting commissions that would have become payable to the underwriters solely in the event that PHPC completed a partnering transaction. Prior to the PHPC Redemption, the Company beneficially owned 31.0% of the equity of PHPC and the net earnings and net assets of PHPC were consolidated within the Company’s financial statements. The remaining 69.0% of the consolidated net earnings and net assets of PHPC, which represented the percentage of economic interest in PHPC held by the public stockholders of PHPC through their ownership of PHPC equity, were allocated to redeemable NCI. All transactions between PHPC and PHPC Sponsor, as well as related financial statement impacts, eliminated in consolidation. On May 11, 2023, PHPC announced that it would not complete a partnering transaction within the Combination Period and that the entity would liquidate and dissolve in accordance with the terms of its amended and restated certificate of incorporation. Subsequent to the decision to liquidate and dissolve, PHPC completed certain winding-up activities, which included writing-off the deferred underwriting commissions as the underwriters agreed to waive their rights to these amounts should a partnering transaction not occur. The Company recorded a $10.7 gain in connection with this write-off, which was recorded in “Other income, net” on the Condensed Consolidated Statements of Operations during both the three and nine months ended June 30, 2023. On May 28, 2023, the PHPC Warrants and the PHPC Private Placement Warrants expired worthless, as PHPC had not completed a partnering transaction before the expiration of the Combination Period. On May 30, 2023, PHPC redeemed all of the outstanding public shares of PHPC Series A Common Stock (the “PHPC Redemption”). Each share of PHPC Series A Common Stock was redeemed for approximately $10.24 per share, representing the per share price equal to the aggregate amount then on deposit in the trust account, including interest earned on the trust account not previously released to pay taxes or dissolution expenses, divided by the number of then outstanding shares of PHPC Series A Common Stock. In connection with the PHPC Redemption, during the three and nine months ended June 30, 2023: • $353.4 of funds held in the trust account immediately prior to the PHPC Redemption were distributed to redeem all of the outstanding shares of PHPC Series A Common Stock. The Company received $40.9 from the PHPC Redemption related to its ownership of 4.0 shares of PHPC Series A Common Stock; and • redeemable NCI of $312.5 immediately prior to the PHPC Redemption was reduced to zero. Subsequent to the PHPC Redemption, PHPC delisted from the New York Stock Exchange and dissolved in June 2023, and all classes of shares of PHPC equity were cancelled, including the PHPC Private Placement Units and the shares of the PHPC Series F Common Stock, which were surrendered by PHPC Sponsor for no consideration. PHPC Sponsor subsequently dissolved in August 2023. The following table summarizes the effects of changes in the Company’s redeemable NCI on the Company’s equity for the three and nine months ended June 30, 2023, which represent the periods ended May 30, 2023, as the Company’s redeemable NCI was reduced to zero upon completion of the PHPC Redemption. Three Months Ended Nine Months Ended Net earnings attributable to redeemable NCI $ 9.3 $ 12.1 Redemption value adjustment (1.9) (5.9) PHPC deemed dividend $ 7.4 $ 6.2 The following table summarizes the changes to the Company’s redeemable NCI for the three and nine months ended June 30, 2023, which represent the periods ended May 30, 2023, as the Company’s redeemable NCI was reduced to zero upon completion of the PHPC Redemption. Three Months Ended Nine Months Ended Beginning of period $ 310.6 $ 306.6 Redemption of PHPC Series A Common Stock (312.5) (312.5) Net earnings attributable to redeemable NCI 9.3 12.1 PHPC deemed dividend (7.4) (6.2) End of period $ — $ —

Business Combinations

Business Combinations	9 Months Ended
	Jun. 30, 2024
Business Combinations [Abstract]
Business Combinations	BUSINESS COMBINATIONS The Company uses the acquisition method of accounting for acquired businesses. Under the acquisition method, the Company’s financial statements reflect the operations of an acquired business starting from the date of acquisition. The assets acquired and liabilities assumed are recorded at their respective estimated fair values at the date of the acquisition based on Level 3 inputs. Any excess of the purchase price over the estimated fair values of the identifiable net assets acquired is recorded as goodwill. Any excess of the estimated fair values of the identifiable net assets acquired over the purchase price is recorded as a gain on bargain purchase. Goodwill represents the value the Company expects to achieve through the implementation of operational synergies, the expansion of the business into new or growing segments of the industry and the addition of new employees. Fiscal 2024 On December 1, 2023, the Company completed its acquisition of substantially all of the assets of Perfection Pet Foods, LLC (“Perfection”) for $235.0, subject to working capital adjustments and other adjustments, resulting in a payment at closing of $238.8. Perfection is a manufacturer and packager of private label and co-manufactured pet food and baked treat products and is reported in the Post Consumer Brands segment. The acquisition was completed using cash on hand, including borrowings under the Revolving Credit Facility (as defined in Note 13 ) . During the third quarter of fiscal 2024, the Company reached a final settlement of net working capital, resulting in an amount received by the Company of $4.6. Based upon the preliminary purchase price allocation, the Company recorded $81.0 of customer relationships, which is being amortized over a weighted-average useful life of 16 years. Net sales and operating profit included in the Condensed Consolidated Statements of Operations attributable to Perfection were $62.1 and $4.2, respectively, for the three months ended June 30, 2024 and $146.7 and $9.1, respectively, for the nine months ended June 30, 2024. Preliminary values of Perfection are measured as of the date of the acquisition, are not yet finalized pending the final purchase price allocation and are subject to change. The goodwill generated by the Company’s Perfection acquisition is expected to be deductible for U.S. income tax purposes. The following table presents the preliminary purchase price allocation, including immaterial measurement period adjustments, related to the Perfection acquisition based upon the fair values of assets acquired and liabilities assumed as of June 30, 2024. Cash and cash equivalents $ 0.3 Receivables, net 40.8 Inventories 21.1 Prepaid expenses and other current assets 0.4 Property, net 69.9 Other intangible assets, net 81.0 Other assets 2.9 Accounts payable (21.5) Other current liabilities (1.6) Other liabilities (1.8) Total identifiable net assets 191.5 Goodwill 42.7 Fair value of total consideration transferred $ 234.2 Also on December 1, 2023, the Company completed its acquisition of Deeside Cereals I Ltd (“Deeside”) for £11.3 (approximately $14.3). The acquisition was completed using cash on hand. Deeside is a producer of private label cereals in the United Kingdom (the “U.K.”) and is reported in the Weetabix segment. Based upon the preliminary purchase price allocation, the Company identified and recorded $20.5 of net assets, which exceeded the purchase price paid for Deeside. As a result, the Company recorded an initial gain on bargain purchase of $6.2 during the first quarter of fiscal 2024. During the third quarter of fiscal 2024, the Company recorded measurement period adjustments related to Deeside’s defined benefit pension plan and deferred taxes, which reduced the acquired Deeside net assets by $0.4. As a result, the Company recorded an adjustment to (gain) on bargain purchase of $0.4 and $ (5.8) Acquisition-related costs for fiscal 2024 acquisitions were immaterial during the three and nine months ended June 30, 2024. Fiscal 2023 On April 28, 2023, the Company completed its acquisition of a portion of The J. M. Smucker Company’s (“Smucker”) pet food business, including brands such as Rachael Ray Nutrish , Nature’s Recipe , 9Lives , Kibbles ’n Bits and Gravy Train , private label pet food assets and certain manufacturing and distribution facilities (collectively, “Pet Food”), facilitating the Company’s entry into the pet food category. The purchase price of the Pet Food acquisition was $1,207.5 which included (i) $700.0 in cash, subject to inventory adjustments, resulting in a payment at closing of $715.5, (ii) 5.4 shares of Post common stock, or $492.3, and (iii) immaterial working capital adjustments. The cash payment was made using cash on hand, including proceeds from the Fourth Incremental Term Loan (as defined in Note 13). Pet Food is reported in the Post Consumer Brands segment. In connection with the Pet Food acquisition, the Company and Smucker entered into a transition services agreement (the “TSA”) pursuant to which Smucker provides certain Pet Food support services to Post for a transition period of 18 months (or up to 24 months at Post’s election) following the close of the acquisition based on the terms set forth in the TSA. Pet Food support services include, but are not limited to, certain sales, marketing, finance, information technology, procurement and supply chain services. TSA fees were $3.5 and $13.0 during the three and nine months ended June 30, 2024 , respectively, and $4.0 during both the three and nine months ended June 30, 2023 . TSA fees were recorded within “Selling, general and administrative expenses” in the Condensed Consolidated Statements of Operations. In accordance with the terms of the TSA, Smucker collects sales receivables from and remits payments to customers and vendors, respectively, in accordance with Smucker’s existing contractual terms. Pet Food receivables and payables are settled between Post and Smucker monthly on a net basis per the terms of the TSA. As of June 30, 2024 and September 30, 2023 , the Company had recorded a net receivable due from Smucker related to the TSA of $39.1 and $35.5, respectively, which was recorded within “Receivables, net” on the Condensed Consolidated Balance Sheets. Unaudited Pro Forma Information The following unaudited pro forma information presents a summary of the results of operations of the Company combined with the results of the fiscal 2024 Perfection acquisition and the fiscal 2023 Pet Food acquisition for the periods presented as if the fiscal 2024 Perfection acquisition had occurred on October 1, 2022 and the fiscal 2023 Pet Food acquisition had occurred on October 1, 2021, along with certain pro forma adjustments. The results of operations for the fiscal 2024 Deeside acquisition were immaterial for presentation within the following unaudited pro forma information. These pro forma adjustments give effect to the amortization of certain definite-lived intangible assets, adjusted depreciation expense based upon the fair value of assets acquired, acquisition-related costs, inventory revaluation adjustments, interest expense, TSA fees and related income taxes. The following unaudited pro forma information has been prepared for comparative purposes only and is not necessarily indicative of the results of operations as they would have been had the Perfection and Pet Food acquisitions occurred on the assumed dates, nor is it necessarily an indication of future operating results. Three Months Ended Nine Months Ended 2024 2023 2024 2023 Pro forma net sales $ 1,947.7 $ 2,058.8 $ 5,953.5 $ 6,146.2 Pro forma net earnings $ 103.5 $ 121.4 $ 296.1 $ 284.9 Pro forma basic earnings per common share $ 1.73 $ 1.95 $ 4.90 $ 4.63 Pro forma diluted earnings per common share $ 1.58 $ 1.80 $ 4.52 $ 4.29

Restructuring (Notes)

Restructuring (Notes)	9 Months Ended
	Jun. 30, 2024
Restructuring [Abstract]
Restructuring	RESTRUCTURING In November 2023, the Company finalized its plan to close its Post Consumer Brands cereal manufacturing facility in Lancaster, Ohio (the “Lancaster Facility”). The transfer of production capabilities to other Company locations and closure of the Lancaster Facility are expected to be completed in the first quarter of fiscal 2025. Restructuring charges and the associated liabilities for employee-related expenses related to the closure of the Lancaster Facility are shown in the following table. Balance, September 30, 2023 $ — Charge to expense 6.6 Cash payments (0.2) Non-cash charges — Balance, June 30, 2024 $ 6.4 Total expected restructuring charges $ 6.7 Cumulative restructuring charges incurred to date 6.6 Remaining expected restructuring charges $ 0.1 Restructuring (adjustments) charges of $(1.1) and $6.6 were included in “Selling, general and administrative expenses” in the Condensed Consolidated Statements of Operations during

Earnings (Loss) Per Share

Earnings (Loss) Per Share	9 Months Ended
	Jun. 30, 2024
Earnings Per Share [Abstract]
(Loss) Earnings per Share	EARNINGS PER SHARE Basic earnings per share is based on the average number of shares of common stock outstanding during the period. Diluted earnings per share is based on the average number of shares used for the basic earnings per share calculation, adjusted for the dilutive effect of stock options, stock appreciation rights and restricted stock units using the “treasury stock” method and convertible senior notes using the “if converted” method. Remeasurements to the redemption value of the redeemable NCI prior to the PHPC Redemption were recognized as a deemed dividend (see Note 3). The Company made an election to treat the portion of the deemed dividend that exceeded fair value as an adjustment to income available to common shareholders for basic and diluted earnings per share. In addition, dilutive net earnings was adjusted for interest expense, net of tax, related to the Company’s convertible senior notes. The following table sets forth the computation of basic and diluted earnings per share. Three Months Ended Nine Months Ended 2024 2023 2024 2023 Net earnings $ 99.8 $ 89.6 $ 285.1 $ 235.6 Impact of redeemable NCI — 1.9 — 11.0 Net earnings for basic earnings per share $ 99.8 $ 91.5 $ 285.1 $ 246.6 Impact of interest expense, net of tax, related to convertible senior notes 2.7 2.7 8.1 8.1 Net earnings for diluted earnings per share $ 102.5 $ 94.2 $ 293.2 $ 254.7 Weighted-average shares for basic earnings per share 60.0 61.6 60.4 59.7 Effect of dilutive securities: Stock options 0.2 0.3 0.3 0.4 Restricted stock units 0.4 0.4 0.4 0.5 Market-based performance restricted stock units 0.9 0.7 0.7 0.6 Earnings-based performance restricted stock units 0.1 0.1 0.1 0.1 Shares issuable upon conversion of convertible senior notes 5.4 5.4 5.4 5.4 Total dilutive securities 7.0 6.9 6.9 7.0 Weighted-average shares for diluted earnings per share 67.0 68.5 67.3 66.7 Earnings per Common Share: Basic $ 1.66 $ 1.49 $ 4.72 $ 4.13 Diluted $ 1.53 $ 1.38 $ 4.36 $ 3.82 The following table presents the securities that have been excluded from the calculation of weighted-average shares for diluted earnings per share as they were anti-dilutive. Three Months Ended Nine Months Ended 2024 2023 2024 2023 Restricted stock units — — — 0.1 Market-based performance restricted stock units — 0.1 — 0.1

Inventories

Inventories	9 Months Ended
	Jun. 30, 2024
Inventory [Abstract]
Inventories	INVENTORIES June 30, September 30, 2023 Raw materials and supplies $ 143.8 $ 155.9 Work in process 25.4 24.4 Finished products 591.2 573.6 Flocks 34.6 36.0 $ 795.0 $ 789.9

Property, net

Property, net	9 Months Ended
	Jun. 30, 2024
Property, Plant and Equipment [Abstract]
Property, net	PROPERTY, NET June 30, September 30, 2023 Property, at cost $ 4,134.8 $ 3,769.4 Accumulated depreciation (1,947.1) (1,748.0) $ 2,187.7 $ 2,021.4

Goodwill (Notes)

Goodwill (Notes)	9 Months Ended
	Jun. 30, 2024
Goodwill [Abstract]
Goodwill	GOODWILL The changes in the carrying amount of goodwill by segment are noted in the following table. Post Consumer Brands Weetabix Foodservice Refrigerated Retail Total Balance, September 30, 2023 Goodwill (gross) $ 2,261.1 $ 854.3 $ 1,355.3 $ 803.7 $ 5,274.4 Accumulated impairment losses (609.1) — — (90.9) (700.0) Goodwill (net) $ 1,652.0 $ 854.3 $ 1,355.3 $ 712.8 $ 4,574.4 Goodwill from acquisition 42.7 — — — 42.7 Currency translation adjustment — 31.6 — — 31.6 Balance, June 30, 2024 Goodwill (gross) $ 2,303.8 $ 885.9 $ 1,355.3 $ 803.7 $ 5,348.7 Accumulated impairment losses (609.1) — — (90.9) (700.0) Goodwill (net) $ 1,694.7 $ 885.9 $ 1,355.3 $ 712.8 $ 4,648.7

Intangible Assets, net

Intangible Assets, net	9 Months Ended
	Jun. 30, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets, net	INTANGIBLE ASSETS, NET June 30, 2024 September 30, 2023 Carrying Accumulated Net Carrying Accumulated Net Subject to amortization: Customer relationships $ 2,622.9 $ (1,045.8) $ 1,577.1 $ 2,535.5 $ (940.7) $ 1,594.8 Trademarks, brands and licensing agreements 886.1 (336.2) 549.9 885.8 (301.3) 584.5 3,509.0 (1,382.0) 2,127.0 3,421.3 (1,242.0) 2,179.3 Not subject to amortization: Trademarks and brands 1,042.0 — 1,042.0 1,033.1 — 1,033.1 $ 4,551.0 $ (1,382.0) $ 3,169.0 $ 4,454.4 $ (1,242.0) $ 3,212.4

Derivative Financial Instrument

Derivative Financial Instruments and Hedging	9 Months Ended
	Jun. 30, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments and Hedging	DERIVATIVE FINANCIAL INSTRUMENTS In the ordinary course of business, the Company is exposed to commodity price risks relating to the purchases of raw materials and supplies, interest rate risks and foreign currency exchange rate risks. The Company utilizes derivative financial instruments, including (but not limited to) futures contracts, option contracts, forward contracts and swaps, to manage certain of these exposures by hedging when it is practical to do so. The Company does not hold or issue financial instruments for speculative or trading purposes. Cash flows associated with all derivatives are reported as cash flows from operating activities in the Condensed Consolidated Statements of Cash Flows, unless the derivative contains an other-than-insignificant financing element, in which case its cash flows are reported as cash flows from financing activities. At June 30, 2024, the Company’s derivative instruments, none of which were designated as hedging instruments under ASC Topic 815, “Derivatives and Hedging,” consisted of: • commodity and energy futures, swaps and option contracts which relate to inputs that generally will be utilized within the next two years; • foreign currency forward contracts (the “FX contracts”) maturing in the next 12 months that have the effect of hedging currency fluctuations between the Euro and the Pound Sterling; and • pay-fixed, receive-variable interest rate swaps maturing in June 2033 that require monthly settlements and have the effect of hedging interest payments on debt expected to be issued but not yet priced. During the nine months ended June 30, 2024, the Company received cash proceeds of $5.2 in connection with the termination of its interest rate swap contracts with a $400.0 notional value. During the nine months ended June 30, 2023, the Company paid $55.1 in connection with the termination of $849.3 notional value of its rate-lock swap contracts, of which $43.5 related to the termination of rate-lock swap contracts that contained other-than-insignificant financing elements and were reported as cash flows from financing activities in the Condensed Consolidated Statements of Cash Flows. The Company also paid $2.1 in connection with the termination of $332.6 notional value of its interest rate swap option, and received cash proceeds of $6.7 in connection with the termination of its interest rate swap contract with a $200.0 notional value. The following table presents the notional amounts of derivative instruments held. June 30, September 30, 2023 Commodity and energy contracts $ 200.8 $ 263.9 FX contracts $ 3.7 $ 3.0 Interest rate swaps $ 300.0 $ 700.0 The following table presents the balance sheet location and fair value of the Company’s derivative instruments. The Company does not offset derivative assets and liabilities within the Condensed Consolidated Balance Sheets. Balance Sheet Location June 30, September 30, 2023 Asset Derivatives: Commodity and energy contracts Prepaid expenses and other current assets $ 2.9 $ 3.7 FX contracts Prepaid expenses and other current assets 0.1 — Interest rate swaps Prepaid expenses and other current assets 3.6 10.6 Commodity and energy contracts Other assets 2.1 — Interest rate swaps Other assets 2.4 11.3 $ 11.1 $ 25.6 Liability Derivatives: Commodity and energy contracts Other current liabilities $ 9.7 $ 16.1 $ 9.7 $ 16.1 The following table presents the statement of operations location and loss (gain) recognized related to the Company’s derivative instruments. Derivative Instruments Statement of Operations Location Three Months Ended June 30, Nine Months Ended 2024 2023 2024 2023 Commodity and energy contracts Cost of goods sold $ 5.6 $ 15.8 $ 30.5 $ 30.1 FX contracts Selling, general and administrative expenses — 0.1 — 0.1 Interest rate swaps (Income) expense on swaps, net (3.1) (17.1) 4.7 (20.4) PHPC Warrants Other income, net — (1.5) — (1.0)

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS The following table presents the Company’s assets and liabilities measured at fair value on a recurring basis and the basis for that measurement according to the levels in the fair value hierarchy in ASC Topic 820, “Fair Value Measurement.” June 30, 2024 September 30, 2023 Total Level 1 Level 2 Total Level 1 Level 2 Assets: Deferred compensation investments $ 15.5 $ 15.5 $ — $ 13.0 $ 13.0 $ — Derivative assets 11.1 — 11.1 25.6 — 25.6 $ 26.6 $ 15.5 $ 11.1 $ 38.6 $ 13.0 $ 25.6 Liabilities: Deferred compensation liabilities $ 45.4 $ — $ 45.4 $ 36.8 $ — $ 36.8 Derivative liabilities 9.7 — 9.7 16.1 — 16.1 $ 55.1 $ — $ 55.1 $ 52.9 $ — $ 52.9 Deferred Compensation The deferred compensation investments are primarily invested in mutual funds, and their fair value is measured using the market approach. These investments are in the same funds, or funds that employ a similar investment strategy, and are purchased in substantially the same amounts, as the participants’ selected notional investment options (excluding Post common stock equivalents), which represent the underlying liabilities to participants in the Company’s deferred compensation plans. Deferred compensation liabilities are recorded at amounts due to participants in cash, based on the fair value of participants’ selected notional investment options (excluding certain Post common stock equivalents to be distributed in shares) using the market approach. Derivatives The Company utilizes the income approach to measure fair value for its commodity and energy derivatives. The income approach uses pricing models that rely on market observable inputs such as yield curves and forward prices. FX contracts are valued using the spot rate less the forward rate multiplied by the notional amount. The Company’s calculation of the fair value of interest rate swaps is derived from a discounted cash flow analysis based on the terms of the contract and the interest rate curve. Refer to Note 11 for the classification of changes in fair value of derivative assets and liabilities measured at fair value on a recurring basis within the Condensed Consolidated Statements of Operations. Equity Securities and Other Fair Value Measurements The Company uses the market approach to measure the fair value of its equity securities, which were immaterial as of both June 30, 2024 and September 30, 2023. The Company’s financial assets and liabilities also include cash and cash equivalents, receivables and accounts payable for which the carrying value approximates fair value due to their short maturities (less than 12 months). The Company does not record its current portion of long-term debt and long-term debt at fair value on the Condensed Consolidated Balance Sheets. The fair values of any outstanding borrowings under the municipal bond and the Revolving Credit Facility (as defined in Note 13) as of June 30, 2024 and September 30, 2023 approximated their carrying values. Based on current market rates, the fair value (Level 2) of the Company’s debt, excluding any outstanding borrowings under the municipal bond and the Revolving Credit Facility, was $5,904.7 and $5,491.5 as of June 30, 2024 and September 30, 2023, respectively, which included $632.8 and $572.6 related to the Company’s convertible senior notes, respectively. Certain assets and liabilities, including property, goodwill and other intangible assets, are measured at fair value on a non-recurring basis using Level 3 inputs.

Long-Term Debt

Long-Term Debt	9 Months Ended
	Jun. 30, 2024
Debt Disclosure [Abstract]
Long-Term Debt	LONG-TERM DEBT The components of “Long-term debt” on the Condensed Consolidated Balance Sheets are presented in the following table. June 30, September 30, 2023 2.50% convertible senior notes maturing August 2027 $ 575.0 $ 575.0 4.50% senior notes maturing September 2031 980.6 1,049.7 4.625% senior notes maturing April 2030 1,385.4 1,385.4 5.50% senior notes maturing December 2029 1,235.0 1,235.0 5.625% senior notes maturing January 2028 939.9 939.9 5.75% senior notes maturing March 2027 — 459.3 6.25% senior secured notes maturing February 2032 1,000.0 — Fourth Incremental Term Loan — 400.0 Revolving Credit Facility 300.0 — Municipal bond 4.2 5.3 $ 6,420.1 $ 6,049.6 Less: Current portion of long-term debt 1.2 1.1 Debt issuance costs, net 45.6 42.0 Plus: Unamortized premium, net 24.5 32.5 Total long-term debt $ 6,397.8 $ 6,039.0
Long-Term Debt - Senior Notes	6.25% Senior Notes On February 20, 2024, the Company issued $1,000.0 principal value of 6.25% senior secured notes (the “6.25% senior notes”) maturing in February 2032. The 6.25% senior notes were issued at par, and the Company received $986.7 after incurring underwriting fees and other fees and expenses of $13.3, which were deferred and are being amortized to interest expense over the term of the 6.25% senior notes. Interest payments on the 6.25% senior notes are due semi-annually each August 15 and February 15, and the maturity date of the 6.25% senior notes is February 15, 2032. The 6.25% senior notes and the related guarantees are secured by first-priority security interests, subject to permitted liens, in collateral that generally includes most of the Company’s and the subsidiary guarantors’ property except for real property and certain other excluded assets. The assets that secure the 6.25% senior notes also secure (and will continue to secure) the Credit Agreement (as defined below) on a pari passu basis. The 6.25% senior notes are fully and unconditionally guaranteed, jointly and severally, on a senior secured basis by each of the Company’s existing and subsequently acquired or organized wholly-owned domestic subsidiaries that guarantee the Credit Agreement or certain of the Company’s other indebtedness, other than immaterial subsidiaries, certain excluded subsidiaries and subsidiaries the Company designates as unrestricted subsidiaries, which such unrestricted subsidiaries include 8th Avenue and its subsidiaries. These guarantees are subject to release in certain circumstances. With a portion of the net proceeds received from the 6.25% senior notes issuance, borrowings under the New Revolving Credit Facility (as defined below) and cash on hand, the Company repaid the outstanding principal balance of the Fourth Incremental Term Loan (as defined below) and all accrued, unpaid interest thereon, redeemed the remainder of the outstanding 5.75% senior notes maturing in March 2027 and all accrued, unpaid interest to the redemption date and repaid the outstanding borrowings under the Old Revolving Credit Facility (as defined below) and all accrued, unpaid interest thereon. For additional information, see the “Credit Agreement,” “Fourth Incremental Term Loan” and “Repayments of Debt” sections below. Convertible Senior Notes On August 12, 2022, the Company issued $575.0 principal value of 2.50% convertible senior notes maturing in August 2027. The initial conversion rate of the 2.50% convertible senior notes is 9.4248 shares of the Company’s common stock per one thousand dollars principal amount of the 2.50% convertible senior notes, which represents an initial conversion price of approximately $106.10 per share of common stock. The conversion rate, and thus the conversion price, may be adjusted under certain circumstances as described in the indenture governing the 2.50% convertible senior notes (the “Convertible Notes Indenture”). The Company may settle conversions by paying or delivering, as applicable, cash, shares of its common stock or a combination of cash and shares of its common stock, at the Company’s election. If a “make-whole fundamental change” (as defined in the Convertible Notes Indenture) occurs, then the Company must in certain circumstances increase the conversion rate for a specified period of time. The 2.50% convertible senior notes may be converted at the holder’s option up to the second scheduled trading day immediately before the maturity date of August 15, 2027 under the following circumstances: • during any calendar quarter (and only during such calendar quarter) if the last reported sale price per share of the Company’s common stock exceeds 130% of the conversion price for each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter; • during the five consecutive business days immediately after any 10 consecutive trading day period (such 10 consecutive trading day period, the “Measurement Period”) in which the trading price per one thousand dollars principal amount of the 2.50% convertible senior notes for each trading day of the Measurement Period was less than 98% of the product of the last reported sale price per share of the Company’s common stock on such trading day and the conversion rate on such trading day; • upon the occurrence of certain corporate events or distributions on the Company’s common stock described in the Convertible Notes Indenture; • if the Company calls the 2.50% convertible senior notes for redemption; and • at any time from, and including, May 15, 2027 until the close of business on the second scheduled trading day immediately before the August 15, 2027 maturity date. If a “fundamental change” (as defined in the Convertible Notes Indenture) occurs, then, except as described in the Convertible Notes Indenture, holders of the 2.50% convertible senior notes may require the Company to repurchase their 2.50% convertible senior notes at a cash repurchase price equal to the principal amount of the 2.50% convertible senior notes to be repurchased, plus accrued and unpaid interest, if any, to, but excluding, the “fundamental change repurchase date” (as defined in the Convertible Notes Indenture). The 2.50% convertible senior notes may be redeemed, in whole or in part (subject to the partial redemption limitation described in the Convertible Notes Indenture), at the Company’s option at any time, and from time to time, on or after August 20, 2025 and on or before the 35th scheduled trading day immediately before August 15, 2027, at a cash redemption price equal to the principal amount of the 2.50% convertible senior notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date, only if the last reported sale price per share of the Company’s common stock exceeds 130% of the conversion price on (i) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date the Company sends the related redemption notice, and (ii) the trading day immediately before the date the Company sends such notice. As of both June 30, 2024 and September 30, 2023, none of the conditions permitting holders to convert their 2.50% convertible senior notes had been satisfied, and no shares of the Company’s common stock had been issued in connection with any conversions of the 2.50% convertible senior notes. The 2.50% convertible senior notes had no embedded features that required separate bifurcation under ASC Topic 815 as of June 30, 2024 or September 30, 2023. As such, the 2.50% convertible senior notes were recorded at the principal amount, net of unamortized issuance costs, on the Condensed Consolidated Balance Sheets as of both June 30, 2024 and September 30, 2023.
Long-Term Debt - Credit Agreement	Credit Agreement On March 18, 2020, the Company entered into a second amended and restated credit agreement (a s amended, including by Joinder Agreement No. 1, Joinder Agreement No. 2, the Third Joinder Agreement (as defined below), the Fourth Joinder Agreement (as defined below) and the Third Amendment (as defined below), as amended, restated or amended and restated, the “Credit Agreement”). Prior to the effective date of the Third Amendment, the Credit Agreement provided for a revolving credit facility in an aggregate principal amount of $750.0 (the “Old Revolving Credit Facility”), with the commitments thereunder to be made available to the Company in U.S. Dollars, Canadian Dollars, Euros and Pounds Sterling. Letters of credit are available under the Credit Agreement in an aggregate amount of up to $75.0 . On February 20, 2024, the Company entered into a third amendment to the Credit Agreement (the “Third Amendment”) by and among the Company, as borrower, certain of the Company’s subsidiaries, as guarantors, Barclays Bank PLC (“Barclays”), as administrative agent under the Credit Agreement prior to the effective date of the Third Amendment, JPMorgan Chase Bank, N.A. (“JPMorgan Chase”), as administrative agent under the Credit Agreement from and after the effective date of the Third Amendment, the institutions constituting the 2024 Revolving Credit Lenders, the L/C Issuers and the Swing Line Lender (as each such term is defined in the Third Amendment). The Company incurred $6.6 of financing fees in connection with the Third Amendment, which were deferred and are being amortized to interest expense over the remaining term of the Credit Agreement . The Third Amendment to the Credit Agreement (i) replaced the Old Revolving Credit Facility with a new revolving credit facility in an aggregate principal amount of $1,000.0 (the “New Revolving Credit Facility”), (ii) extended the maturity date of the New Revolving Credit Facility to February 20, 2029, provided that if on October 16, 2027 the Company’s 5.625% senior notes maturing in January 2028 have not been redeemed in full in cash or refinanced and replaced in full with notes and/or loans maturing at least 91 days after February 20, 2029, then the maturity date of the New Revolving Credit Facility will be October 16, 2027 and (iii) modified certain other terms, conditions and provisions of the Credit Agreement, including transferring the administrative agent role from Barclays to JPMorgan Chase. The term “Revolving Credit Facility” used herein generally refers to the Old Revolving Credit Facility prior to the Third Amendment and the New Revolving Credit Facility subsequent to the Third Amendment. Borrowings in U.S. Dollars under the New Revolving Credit Facility bear interest, at the option of the Company, at an annual rate equal to either (a) the adjusted term SOFR rate (as defined in the Credit Agreement) or (b) the base rate determined by reference to the highest of (i) the prime rate, (ii) the NYFRB Rate (as defined in the Credit Agreement) plus 0.50% per annum and (iii) the one-month adjusted term SOFR rate plus 1.00% per annum, in each case plus an applicable margin, which is determined by reference to the secured net leverage ratio (as defined in the Credit Agreement), with the applicable margin for adjusted term SOFR rate loans and base rate loans being (i) 2.00% and 1.00%, respectively, if the secured net leverage ratio is greater than or equal to 3.00:1.00, (ii) 1.75% and 0.75%, respectively, if the secured net leverage ratio is less than 3.00:1.00 and greater than or equal to 1.50:1.00 or (iii) 1.50% and 0.50%, respectively, if the secured net leverage ratio is less than 1.50:1.00. Commitment fees on the daily unused amount of commitments under the Revolving Credit Facility accrue at a rate of 0.375% if the Company’s secured net leverage ratio is greater than or equal to 3.00:1.00, and accrue at a rate of 0.25% if the Company’s secured net leverage ratio is less than 3.00:1.00. During the nine months ended June 30, 2024, the Company borrowed $645.0 and repaid $345.0 under the Revolving Credit Facility. There were no borrowings or repayments under the Revolving Credit Facility during the nine months ended June 30, 2023 . As of June 30, 2024, the Revolving Credit Facility had outstanding borrowings of $300.0, outstanding letters of credit of $20.0 and an available borrowing capacity of $680.0 . As of September 30, 2023, the Revolving Credit Facility had no outstanding borrowings, outstanding letters of credit of $19.7 and an available borrowing capacity of $730.3 . As of June 30, 2024, the interest rate on the outstanding borrowings under the Revolving Credit Facility was 6.93%. The Credit Agreement provides for potential incremental revolving and term facilities at the request of the Company and at the discretion of the lenders or other persons providing such incremental facilities, in each case on terms to be determined, and also permits the Company to incur other secured or unsecured debt, in all cases subject to conditions and limitations specified in the Credit Agreement. The Credit Agreement provides for customary events of default, including material breach of representations and warranties, failure to make required payments, failure to comply with certain agreements or covenants, failure to pay or default under certain other indebtedness in excess of $125.0, certain events of bankruptcy and insolvency, inability to pay debts, the occurrence of one or more unstayed or undischarged judgments in excess of $125.0, attachments issued against all or any material part of the Company’s property, certain events under the Employee Retirement Income Security Act of 1974, a change of control (as defined in the Credit Agreement), the invalidity of any loan document and the failure of the collateral documents to create a valid and perfected first priority lien (subject to certain permitted liens). Upon the occurrence and during the continuance of an event of default, the maturity of the loans under the Credit Agreement may accelerate and the agent and lenders under the Credit Agreement may exercise other rights and remedies available at law or under the loan documents, including with respect to the collateral and guarantees of the Company’s obligations under the Credit Agreement.
Long-Term Debt -Third Incremental Term Loan	Third Incremental Term Loan On November 18, 2022, the Company entered into Joinder Agreement No. 3 (the “Third Joinder Agreement”) by and among the Company, as borrower, certain of the Company’s subsidiaries, as guarantors, J.P. Morgan Securities LLC (“J.P. Morgan”), as lender, Barclays, as administrative agent, and JPMorgan Chase, as sub-agent to the administrative agent. The Third Joinder Agreement provided for an incremental term loan (the “Third Incremental Term Loan”) of $130.0 under the Company’s Credit Agreement, which the Company borrowed in full on November 18, 2022. On November 21, 2022, the Company and J.P. Morgan entered into an exchange agreement pursuant to which the Company transferred the remaining shares of BellRing common stock it held from its previous transactions related to the distribution of a portion of its interest in BellRing, which occurred in fiscal 2022, to J.P. Morgan to repay $99.9 in aggregate principal amount of the Third Incremental Term Loan (such exchange, the “Fiscal 2023 Debt-for-Equity Exchange”). Following the completion of the Fiscal 2023 Debt-for-Equity Exchange, the Company no longer held shares of BellRing common stock. On November 25, 2022, the Company repaid the remaining principal balance of $30.1 of the Third Incremental Term Loan using cash on hand. For additional information, see “Repayments of Debt” below.
Long-Term Debt - Fourth Incremental Term Loan	Fourth Incremental Term Loan On April 26, 2023, the Company entered into Joinder Agreement No. 4 (the “Fourth Joinder Agreement”) by and among the Company, as borrower, certain of the Company’s subsidiaries, as guarantors, the institutions party to the Fourth Joinder Agreement as lenders and Barclays, as the administrative agent. The Fourth Joinder Agreement provided for an incremental term loan (the “Fourth Incremental Term Loan”) of $400.0 under the Credit Agreement, which the Company borrowed in full on April 26, 2023. On February 20, 2024, the Company repaid the outstanding principal balance of the Fourth Incremental Term Loan and all accrued, unpaid interest thereon using a portion of the net proceeds from the 6.25% senior notes issuance. For additional information, see “Repayments of Debt” below. Interest on the Fourth Incremental Term Loan accrued, at the Company’s option, at the base rate (as defined in the Credit Agreement) plus 1.25% per annum or the adjusted term SOFR rate plus 2.25% per annum. Interest was payable quarterly for loans bearing interest based upon the base rate and either monthly or every three months (depending on the applicable interest period) for loans bearing interest based upon the adjusted term SOFR rate. As of September 30, 2023, the interest rate on the Fourth Incremental Term Loan was 7.67%.
Long-Term Debt - Muni Bond	Municipal Bond In connection with the construction of a filtration system at the Company’s potato plant in Chaska, Minnesota, the Company incurred debt that guarantees the repayment of certain industrial revenue bonds used to finance the construction of the project. Principal payments are due annually on March 1, and interest payments are due semi-annually each March 1 and September 1. The debt matures on March 1, 2028.
Long-Term Debt - Repayments & Other	Repayments of Debt The following table presents the Company’s (i) principal repayments of debt, which, net of discounts, were included in the Condensed Consolidated Statements of Cash Flows, (ii) principal amounts of debt exchanged (refer to the “Third Incremental Term Loan” section above), which were not included in the Condensed Consolidated Statements of Cash Flows and (iii) the associated (gain) loss related to such repayments and exchanges included in “Gain on extinguishment of debt, net” in the Condensed Consolidated Statements of Operations. Gain on Extinguishment of Debt, net Debt Instrument Principal Amount Repaid Principal Amount Exchanged Debt Discounts (Received) / Premiums Paid Write-off of Debt Issuance Costs Write-off of Unamortized Premiums Three Months Ended June 30, 2024 4.50% senior notes $ 18.0 $ — $ (1.9) $ 0.1 $ — Total $ 18.0 $ — $ (1.9) $ 0.1 $ — Three Months Ended June 30, 2023 4.50% senior notes $ 20.7 $ — $ (3.0) $ 0.1 $ — 4.625% senior notes 29.3 — (3.4) 0.2 (0.3) Total $ 50.0 $ — $ (6.4) $ 0.3 $ (0.3) Nine Months Ended June 30, 2024 4.50% senior notes $ 69.1 $ — $ (7.9) $ 0.5 $ — 5.75% senior notes 459.3 — 4.4 1.6 (4.6) Municipal bond 1.1 — — — — Fourth Incremental Term Loan 400.0 — — 1.4 — Revolving Credit Facility 345.0 — — — — Total $ 1,274.5 $ — $ (3.5) $ 3.5 $ (4.6) Nine Months Ended June 30, 2023 4.50% senior notes $ 141.2 $ — $ (19.9) $ 1.1 $ — 4.625% senior notes 29.3 — (3.4) 0.2 (0.3) Municipal bond 1.1 — — — — Third Incremental Term Loan 30.1 99.9 — 1.1 — Total $ 201.7 $ 99.9 $ (23.3) $ 2.4 $ (0.3) Debt Covenants Under the terms of the Credit Agreement, the Company is required to comply with a financial covenant consisting of a secured net leverage ratio not to exceed 4.25:1.00 measured as of the last day of any fiscal quarter if, as of the last day of such fiscal quarter, the aggregate outstanding amount of all revolving credit loans, swing line loans and letter of credit obligations (subject to certain exceptions specified in the Credit Agreement) exceeds 30% of the Company’s revolving credit commitments. As of June 30, 2024, the Company was in compliance with this financial covenant. The Credit Agreement provides for incremental revolving and term loan facilities, and also permits other secured or unsecured debt, if, among other conditions, certain financial ratios are met, as defined and specified in the Credit Agreement.

Commitments and Contingencies (

Commitments and Contingencies (Notes)	9 Months Ended
	Jun. 30, 2024
Legal Proceedings [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Legal Proceedings The Company is subject to various legal proceedings and actions arising in the normal course of business. In the opinion of management, based upon the information presently known, the ultimate liability, if any, arising from such pending legal proceedings, as well as from asserted legal claims and known potential legal claims which are likely to be asserted, taking into account established accruals for estimated liabilities (if any), are not expected to be material individually or in the aggregate to the consolidated financial condition, results of operations or cash flows of the Company. In addition, although it is difficult to estimate the potential financial impact of actions regarding expenditures for compliance with regulatory matters, in the opinion of management, based upon the information currently available, the ultimate liability arising from such compliance matters is not expected to be material to the consolidated financial condition, results of operations or cash flows of the Company.

Pension and Other Postretiremen

Pension and Other Postretirement Benefits	9 Months Ended
	Jun. 30, 2024
Pension and Other Postretirement Benefits Cost (Reversal of Cost) [Abstract]
Pension and Other Postretirement benefits	PENSION AND OTHER POSTRETIREMENT BENEFITS The Company maintains qualified defined benefit plans in the U.S., the U.K. and Canada for certain employees primarily within its Post Consumer Brands and Weetabix segments. Certain of the Company’s employees are eligible to participate in the Company’s postretirement benefit plans (partially subsidized retiree health and life insurance). On February 16, 2024, the Company adopted the Post Holdings, Inc. 2024 Supplemental Executive Retirement Plan (the “SERP”), an unfunded, non-qualified defined benefit retirement plan for certain management employees of the Company, including its named executive officers, that was effective on February 19, 2024. The SERP is a supplemental program that provides a cash balance benefit to each participant. The SERP participants were credited with an opening credit, based on years of past service with the Company, and accrue ongoing benefits with a pay credit equal to a percentage of certain of the participant’s annualized compensation. The Company recorded an initial projected benefit obligation of $8.3 related to the SERP during the second quarter of fiscal 2024, which was included in “Accumulated other comprehensive loss” on the Condensed Consolidated Balance Sheets at June 30, 2024. Net periodic benefit costs related to the SERP during the three and nine months ended June 30, 2024 were immaterial. Amounts for the Canadian plans and the SERP are included in the North America disclosures and are not disclosed separately because they do not constitute a significant portion of the combined amounts. The following tables present the components of net periodic benefit cost (income) for the pension plans. Service cost was reported in “Cost of goods sold” and “Selling, general and administrative expenses” and all other components of net periodic benefit cost (income) were reported in “Other income, net” in the Condensed Consolidated Statements of Operations. North America Three Months Ended Nine Months Ended 2024 2023 2024 2023 Service cost $ 0.7 $ 0.6 $ 1.7 $ 1.7 Interest cost 1.5 1.3 4.3 3.9 Expected return on plan assets (2.0) (1.9) (6.1) (5.7) Recognized net actuarial gain (0.1) — (0.3) (0.1) Recognized prior service cost 0.3 — 0.4 0.1 Net periodic benefit cost (income) $ 0.4 $ — $ — $ (0.1) Other International Three Months Ended Nine Months Ended 2024 2023 2024 2023 Service cost $ 0.1 $ — $ 0.2 $ — Interest cost 6.5 6.0 19.2 17.3 Expected return on plan assets (8.8) (7.9) (26.0) (22.9) Recognized net actuarial loss — — 0.1 0.1 Recognized prior service cost 0.1 0.1 0.3 0.3 Net periodic benefit income $ (2.1) $ (1.8) $ (6.2) $ (5.2) The following table presents the components of net periodic benefit cost (income) for the North American other postretirement benefit plans. Service cost was reported in “Cost of goods sold” and “Selling, general and administrative expenses” and all other components of net periodic benefit cost (income) were reported in “Other income, net” in the Condensed Consolidated Statements of Operations. Three Months Ended Nine Months Ended 2024 2023 2024 2023 Service cost $ 0.1 $ 0.1 $ 0.2 $ 0.2 Interest cost 0.7 0.6 2.0 1.9 Recognized net actuarial gain (0.3) (0.1) (0.8) (0.4) Recognized prior service credit (0.2) (1.2) (0.5) (3.5) Net periodic benefit cost (income) $ 0.3 $ (0.6) $ 0.9 $ (1.8)

Shareholders' Equity

Shareholders' Equity	9 Months Ended
	Jun. 30, 2024
Equity [Abstract]
Shareholders' Equity	SHAREHOLDERS’ EQUITY The following table summarizes the Company’s repurchases of its common stock. Three Months Ended Nine Months Ended 2024 2023 2024 2023 Shares repurchased 2.0 1.9 2.5 2.9 Average price per share (a) $ 104.18 $ 86.64 $ 100.71 $ 86.91 Total share repurchase costs (b) $ 209.7 $ 166.8 $ 254.5 $ 250.5 (a) Average price per share excludes accrued excise tax and broker’s commissions, which are included in “Total share repurchase costs” within this table. (b) “Purchases of treasury stock” in the Condensed Consolidated Statements of Cash Flows for the nine months ended June 30, 2024 excluded $4.0 of repurchases of common stock that were accrued in the third quarter of fiscal 2024 but did not settle until July 2024 and $1.8 of accrued excise tax that had not been paid as of June 30, 2024. “Purchases of treasury stock” in the Condensed Consolidated Statements of Cash Flows for the nine months ended June 30, 2023 excluded $8.1 of repurchases of common stock that were accrued in the third quarter of fiscal 2023 but did not settle until July 2023. In February 2024, the Company entered into a structured share repurchase arrangement, which consisted of purchased call options with a $0 strike price per option and written call options with a $99.45 strike price per option. The Company paid $50.0 of net premiums in connection with the contracts, which were included in “Payment for share repurchase contracts” in the Condensed Consolidated Statements of Cash Flows for the nine months ended June 30, 2024. Upon settlement, the Company had the right to receive approximately 0.5 shares of Post common stock, to be settled in shares or cash, at the option of the Company. The contracts settled in May 2024, which resulted in the Company receiving cash proceeds of $50.9, which were included in “Proceeds from share repurchase contracts” in the Condensed Consolidated Statements of Cash Flows for the nine months ended June 30, 2024.

Segments

Segments	9 Months Ended
	Jun. 30, 2024
Segment Reporting [Abstract]
Segments	SEGMENTS At June 30, 2024, the Company managed and reported operating results through the following four reportable segments: • Post Consumer Brands : North American RTE cereal, pet food and peanut butter; • Weetabix: primarily U.K. RTE cereal, muesli and protein-based shakes; • Foodservice: primarily egg and potato products; and • Refrigerated Retail: primarily side dish, egg, cheese and sausage products. Due to the level of integration between the Foodservice and Refrigerated Retail segments, it is impracticable to present total assets separately for each segment. An allocation has been made between the two segments for depreciation based on inventory costing. Amounts reported for Corporate in the table below include any amounts attributable to PHPC prior to the PHPC Redemption in the third quarter of fiscal 2023 (see Note 3). Management evaluates each segment’s performance based on its segment profit, which for all segments is its earnings/loss before income taxes and equity method earnings/loss before impairment of property, goodwill and other intangible assets, facility closure related costs, restructuring expenses, gain/loss on assets and liabilities held for sale, gain/loss on sale of businesses and facilities, gain on/adjustment to bargain purchase, interest expense and other unallocated corporate income and expenses. The following tables present information about the Company’s reportable segments. In addition, the tables present net sales by product. Three Months Ended Nine Months Ended 2024 2023 2024 2023 Net Sales Post Consumer Brands $ 1,008.1 $ 871.3 $ 3,062.2 $ 2,025.1 Weetabix 136.1 134.2 403.2 377.2 Foodservice 589.1 622.7 1,711.0 1,856.4 Refrigerated Retail 214.4 230.7 735.7 786.4 Eliminations and Corporate — 0.5 0.5 0.5 Total $ 1,947.7 $ 1,859.4 $ 5,912.6 $ 5,045.6 Segment Profit Post Consumer Brands $ 128.6 $ 83.0 $ 401.0 $ 237.8 Weetabix 24.1 17.9 63.2 58.8 Foodservice 89.6 107.7 229.8 264.9 Refrigerated Retail 5.1 18.0 63.1 57.2 Total segment profit 247.4 226.6 757.1 618.7 General corporate expenses and other 41.9 52.3 145.9 139.9 Interest expense, net 78.8 72.7 236.9 202.4 Gain on extinguishment of debt, net (1.8) (6.4) (4.6) (21.2) (Income) expense on swaps, net (3.1) (17.1) 4.7 (20.4) Earnings before income taxes and equity method loss $ 131.6 $ 125.1 $ 374.2 $ 318.0 Net sales by product Cereal $ 677.5 $ 700.8 $ 2,039.3 $ 2,028.5 Eggs and egg products 542.2 591.1 1,582.0 1,769.2 Pet food 428.9 275.3 1,316.2 275.3 Side dishes (including potato products) 174.8 171.0 576.6 561.0 Cheese and dairy 39.9 42.9 129.9 143.9 Sausage 34.2 35.5 123.4 127.8 Peanut butter 28.8 20.0 83.5 74.9 Protein-based products 9.8 9.4 23.3 23.6 Other 11.6 13.4 38.4 42.2 Eliminations — — — (0.8) Total $ 1,947.7 $ 1,859.4 $ 5,912.6 $ 5,045.6 Depreciation and amortization Post Consumer Brands $ 52.5 $ 44.1 $ 153.7 $ 109.2 Weetabix 10.2 9.2 29.6 26.6 Foodservice 33.0 31.8 98.8 95.5 Refrigerated Retail 17.9 19.1 53.5 57.4 Total segment depreciation and amortization 113.6 104.2 335.6 288.7 Corporate 7.1 2.3 17.1 4.6 Total $ 120.7 $ 106.5 $ 352.7 $ 293.3 Assets June 30, September 30, 2023 Post Consumer Brands $ 4,992.0 $ 4,782.2 Weetabix 1,831.1 1,737.8 Foodservice and Refrigerated Retail 4,867.1 4,921.6 Corporate 438.3 205.1 Total assets $ 12,128.5 $ 11,646.7

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Pay vs Performance Disclosure
Net Earnings	$ 99.8	$ 89.6	$ 285.1	$ 235.6

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended	9 Months Ended
	Jun. 30, 2024	Jun. 30, 2024
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		OTHER INFORMATION. Rule 10b5-1 and Non-Rule 10b5-1 Trading Arrangements During the three months ended June 30, 2024, no director or “officer,” as defined in Rule 16a-1(f) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), of the Company adopted or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408 of Regulation S-K.
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Noncontrolling Interests, Equ_2

Noncontrolling Interests, Equity Interests and Related Party Transactions (Tables)	9 Months Ended
	Jun. 30, 2023
Equity Method Investments and Joint Ventures [Abstract]
Effects of changes in ownership of PHPC on Post equity	Three Months Ended Nine Months Ended Net earnings attributable to redeemable NCI $ 9.3 $ 12.1 Redemption value adjustment (1.9) (5.9) PHPC deemed dividend $ 7.4 $ 6.2
Redeemable Noncontrolling Interest	Three Months Ended Nine Months Ended Beginning of period $ 310.6 $ 306.6 Redemption of PHPC Series A Common Stock (312.5) (312.5) Net earnings attributable to redeemable NCI 9.3 12.1 PHPC deemed dividend (7.4) (6.2) End of period $ — $ —

Business Combinations (Tables)

Business Combinations (Tables)	9 Months Ended
	Jun. 30, 2024
Business Combinations [Abstract]
Opening Balance Sheets	The following table presents the preliminary purchase price allocation, including immaterial measurement period adjustments, related to the Perfection acquisition based upon the fair values of assets acquired and liabilities assumed as of June 30, 2024. Cash and cash equivalents $ 0.3 Receivables, net 40.8 Inventories 21.1 Prepaid expenses and other current assets 0.4 Property, net 69.9 Other intangible assets, net 81.0 Other assets 2.9 Accounts payable (21.5) Other current liabilities (1.6) Other liabilities (1.8) Total identifiable net assets 191.5 Goodwill 42.7 Fair value of total consideration transferred $ 234.2
Pro Forma Information	Three Months Ended Nine Months Ended 2024 2023 2024 2023 Pro forma net sales $ 1,947.7 $ 2,058.8 $ 5,953.5 $ 6,146.2 Pro forma net earnings $ 103.5 $ 121.4 $ 296.1 $ 284.9 Pro forma basic earnings per common share $ 1.73 $ 1.95 $ 4.90 $ 4.63 Pro forma diluted earnings per common share $ 1.58 $ 1.80 $ 4.52 $ 4.29

Restructuring (Tables)

Restructuring (Tables)	9 Months Ended
	Jun. 30, 2024
Restructuring [Abstract]
Restructuring charges and related liabilities	Restructuring charges and the associated liabilities for employee-related expenses related to the closure of the Lancaster Facility are shown in the following table. Balance, September 30, 2023 $ — Charge to expense 6.6 Cash payments (0.2) Non-cash charges — Balance, June 30, 2024 $ 6.4 Total expected restructuring charges $ 6.7 Cumulative restructuring charges incurred to date 6.6 Remaining expected restructuring charges $ 0.1

Earnings (Loss) Per Share (Tabl

Earnings (Loss) Per Share (Tables)	9 Months Ended
	Jun. 30, 2024
Earnings Per Share [Abstract]
Computation of basic and diluted (loss) earnings per share	Three Months Ended Nine Months Ended 2024 2023 2024 2023 Net earnings $ 99.8 $ 89.6 $ 285.1 $ 235.6 Impact of redeemable NCI — 1.9 — 11.0 Net earnings for basic earnings per share $ 99.8 $ 91.5 $ 285.1 $ 246.6 Impact of interest expense, net of tax, related to convertible senior notes 2.7 2.7 8.1 8.1 Net earnings for diluted earnings per share $ 102.5 $ 94.2 $ 293.2 $ 254.7 Weighted-average shares for basic earnings per share 60.0 61.6 60.4 59.7 Effect of dilutive securities: Stock options 0.2 0.3 0.3 0.4 Restricted stock units 0.4 0.4 0.4 0.5 Market-based performance restricted stock units 0.9 0.7 0.7 0.6 Earnings-based performance restricted stock units 0.1 0.1 0.1 0.1 Shares issuable upon conversion of convertible senior notes 5.4 5.4 5.4 5.4 Total dilutive securities 7.0 6.9 6.9 7.0 Weighted-average shares for diluted earnings per share 67.0 68.5 67.3 66.7 Earnings per Common Share: Basic $ 1.66 $ 1.49 $ 4.72 $ 4.13 Diluted $ 1.53 $ 1.38 $ 4.36 $ 3.82
Antidilutive Securities Excluded from Computation of Diluted (Loss) Earnings Per Share	Three Months Ended Nine Months Ended 2024 2023 2024 2023 Restricted stock units — — — 0.1 Market-based performance restricted stock units — 0.1 — 0.1

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Jun. 30, 2024
Inventory [Abstract]
Inventories	June 30, September 30, 2023 Raw materials and supplies $ 143.8 $ 155.9 Work in process 25.4 24.4 Finished products 591.2 573.6 Flocks 34.6 36.0 $ 795.0 $ 789.9

Property, net (Tables)

Property, net (Tables)	9 Months Ended
	Jun. 30, 2024
Property, Plant and Equipment [Abstract]
Property, net	June 30, September 30, 2023 Property, at cost $ 4,134.8 $ 3,769.4 Accumulated depreciation (1,947.1) (1,748.0) $ 2,187.7 $ 2,021.4

Goodwill (Tables)

Goodwill (Tables)	9 Months Ended
	Jun. 30, 2024
Goodwill
Carrying Amount of Goodwill	Post Consumer Brands Weetabix Foodservice Refrigerated Retail Total Balance, September 30, 2023 Goodwill (gross) $ 2,261.1 $ 854.3 $ 1,355.3 $ 803.7 $ 5,274.4 Accumulated impairment losses (609.1) — — (90.9) (700.0) Goodwill (net) $ 1,652.0 $ 854.3 $ 1,355.3 $ 712.8 $ 4,574.4 Goodwill from acquisition 42.7 — — — 42.7 Currency translation adjustment — 31.6 — — 31.6 Balance, June 30, 2024 Goodwill (gross) $ 2,303.8 $ 885.9 $ 1,355.3 $ 803.7 $ 5,348.7 Accumulated impairment losses (609.1) — — (90.9) (700.0) Goodwill (net) $ 1,694.7 $ 885.9 $ 1,355.3 $ 712.8 $ 4,648.7

Intangible Assets, net (Tables)

Intangible Assets, net (Tables)	9 Months Ended
	Jun. 30, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
Total Intangible Assets	June 30, 2024 September 30, 2023 Carrying Accumulated Net Carrying Accumulated Net Subject to amortization: Customer relationships $ 2,622.9 $ (1,045.8) $ 1,577.1 $ 2,535.5 $ (940.7) $ 1,594.8 Trademarks, brands and licensing agreements 886.1 (336.2) 549.9 885.8 (301.3) 584.5 3,509.0 (1,382.0) 2,127.0 3,421.3 (1,242.0) 2,179.3 Not subject to amortization: Trademarks and brands 1,042.0 — 1,042.0 1,033.1 — 1,033.1 $ 4,551.0 $ (1,382.0) $ 3,169.0 $ 4,454.4 $ (1,242.0) $ 3,212.4

Derivative Financial Instrume_2

Derivative Financial Instruments and Hedging (Tables)	9 Months Ended
	Jun. 30, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Notional amounts of derivatives held	June 30, September 30, 2023 Commodity and energy contracts $ 200.8 $ 263.9 FX contracts $ 3.7 $ 3.0 Interest rate swaps $ 300.0 $ 700.0
Derivative Instruments in Condensed Consolidated Balance Sheets	Balance Sheet Location June 30, September 30, 2023 Asset Derivatives: Commodity and energy contracts Prepaid expenses and other current assets $ 2.9 $ 3.7 FX contracts Prepaid expenses and other current assets 0.1 — Interest rate swaps Prepaid expenses and other current assets 3.6 10.6 Commodity and energy contracts Other assets 2.1 — Interest rate swaps Other assets 2.4 11.3 $ 11.1 $ 25.6 Liability Derivatives: Commodity and energy contracts Other current liabilities $ 9.7 $ 16.1 $ 9.7 $ 16.1
Effect of Derivative Instruments on the Condensed Consolidated Statements of Operations and Condensed Consolidated Statements of Other Comprehensive Income	The following table presents the statement of operations location and loss (gain) recognized related to the Company’s derivative instruments. Derivative Instruments Statement of Operations Location Three Months Ended June 30, Nine Months Ended 2024 2023 2024 2023 Commodity and energy contracts Cost of goods sold $ 5.6 $ 15.8 $ 30.5 $ 30.1 FX contracts Selling, general and administrative expenses — 0.1 — 0.1 Interest rate swaps (Income) expense on swaps, net (3.1) (17.1) 4.7 (20.4) PHPC Warrants Other income, net — (1.5) — (1.0)

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Jun. 30, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets and liabilities measured at fair value on a recurring basis	June 30, 2024 September 30, 2023 Total Level 1 Level 2 Total Level 1 Level 2 Assets: Deferred compensation investments $ 15.5 $ 15.5 $ — $ 13.0 $ 13.0 $ — Derivative assets 11.1 — 11.1 25.6 — 25.6 $ 26.6 $ 15.5 $ 11.1 $ 38.6 $ 13.0 $ 25.6 Liabilities: Deferred compensation liabilities $ 45.4 $ — $ 45.4 $ 36.8 $ — $ 36.8 Derivative liabilities 9.7 — 9.7 16.1 — 16.1 $ 55.1 $ — $ 55.1 $ 52.9 $ — $ 52.9

Long-Term Debt (Tables)

Long-Term Debt (Tables)	9 Months Ended
	Jun. 30, 2024
Debt Disclosure [Abstract]
Long-term Debt	June 30, September 30, 2023 2.50% convertible senior notes maturing August 2027 $ 575.0 $ 575.0 4.50% senior notes maturing September 2031 980.6 1,049.7 4.625% senior notes maturing April 2030 1,385.4 1,385.4 5.50% senior notes maturing December 2029 1,235.0 1,235.0 5.625% senior notes maturing January 2028 939.9 939.9 5.75% senior notes maturing March 2027 — 459.3 6.25% senior secured notes maturing February 2032 1,000.0 — Fourth Incremental Term Loan — 400.0 Revolving Credit Facility 300.0 — Municipal bond 4.2 5.3 $ 6,420.1 $ 6,049.6 Less: Current portion of long-term debt 1.2 1.1 Debt issuance costs, net 45.6 42.0 Plus: Unamortized premium, net 24.5 32.5 Total long-term debt $ 6,397.8 $ 6,039.0
Repayments of Long-term Debt	The following table presents the Company’s (i) principal repayments of debt, which, net of discounts, were included in the Condensed Consolidated Statements of Cash Flows, (ii) principal amounts of debt exchanged (refer to the “Third Incremental Term Loan” section above), which were not included in the Condensed Consolidated Statements of Cash Flows and (iii) the associated (gain) loss related to such repayments and exchanges included in “Gain on extinguishment of debt, net” in the Condensed Consolidated Statements of Operations. Gain on Extinguishment of Debt, net Debt Instrument Principal Amount Repaid Principal Amount Exchanged Debt Discounts (Received) / Premiums Paid Write-off of Debt Issuance Costs Write-off of Unamortized Premiums Three Months Ended June 30, 2024 4.50% senior notes $ 18.0 $ — $ (1.9) $ 0.1 $ — Total $ 18.0 $ — $ (1.9) $ 0.1 $ — Three Months Ended June 30, 2023 4.50% senior notes $ 20.7 $ — $ (3.0) $ 0.1 $ — 4.625% senior notes 29.3 — (3.4) 0.2 (0.3) Total $ 50.0 $ — $ (6.4) $ 0.3 $ (0.3) Nine Months Ended June 30, 2024 4.50% senior notes $ 69.1 $ — $ (7.9) $ 0.5 $ — 5.75% senior notes 459.3 — 4.4 1.6 (4.6) Municipal bond 1.1 — — — — Fourth Incremental Term Loan 400.0 — — 1.4 — Revolving Credit Facility 345.0 — — — — Total $ 1,274.5 $ — $ (3.5) $ 3.5 $ (4.6) Nine Months Ended June 30, 2023 4.50% senior notes $ 141.2 $ — $ (19.9) $ 1.1 $ — 4.625% senior notes 29.3 — (3.4) 0.2 (0.3) Municipal bond 1.1 — — — — Third Incremental Term Loan 30.1 99.9 — 1.1 — Total $ 201.7 $ 99.9 $ (23.3) $ 2.4 $ (0.3)

Pension and Other Postretirem_2

Pension and Other Postretirement Benefits (Tables)	9 Months Ended
	Jun. 30, 2024
Pension and Other Postretirement Benefits Cost (Reversal of Cost) [Abstract]
Schedule of Net Benefit Costs	The following tables present the components of net periodic benefit cost (income) for the pension plans. Service cost was reported in “Cost of goods sold” and “Selling, general and administrative expenses” and all other components of net periodic benefit cost (income) were reported in “Other income, net” in the Condensed Consolidated Statements of Operations. North America Three Months Ended Nine Months Ended 2024 2023 2024 2023 Service cost $ 0.7 $ 0.6 $ 1.7 $ 1.7 Interest cost 1.5 1.3 4.3 3.9 Expected return on plan assets (2.0) (1.9) (6.1) (5.7) Recognized net actuarial gain (0.1) — (0.3) (0.1) Recognized prior service cost 0.3 — 0.4 0.1 Net periodic benefit cost (income) $ 0.4 $ — $ — $ (0.1) Other International Three Months Ended Nine Months Ended 2024 2023 2024 2023 Service cost $ 0.1 $ — $ 0.2 $ — Interest cost 6.5 6.0 19.2 17.3 Expected return on plan assets (8.8) (7.9) (26.0) (22.9) Recognized net actuarial loss — — 0.1 0.1 Recognized prior service cost 0.1 0.1 0.3 0.3 Net periodic benefit income $ (2.1) $ (1.8) $ (6.2) $ (5.2) The following table presents the components of net periodic benefit cost (income) for the North American other postretirement benefit plans. Service cost was reported in “Cost of goods sold” and “Selling, general and administrative expenses” and all other components of net periodic benefit cost (income) were reported in “Other income, net” in the Condensed Consolidated Statements of Operations. Three Months Ended Nine Months Ended 2024 2023 2024 2023 Service cost $ 0.1 $ 0.1 $ 0.2 $ 0.2 Interest cost 0.7 0.6 2.0 1.9 Recognized net actuarial gain (0.3) (0.1) (0.8) (0.4) Recognized prior service credit (0.2) (1.2) (0.5) (3.5) Net periodic benefit cost (income) $ 0.3 $ (0.6) $ 0.9 $ (1.8)

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	9 Months Ended
	Jun. 30, 2024
Equity [Abstract]
Repurchases of Common Stock	Three Months Ended Nine Months Ended 2024 2023 2024 2023 Shares repurchased 2.0 1.9 2.5 2.9 Average price per share (a) $ 104.18 $ 86.64 $ 100.71 $ 86.91 Total share repurchase costs (b) $ 209.7 $ 166.8 $ 254.5 $ 250.5 (a) Average price per share excludes accrued excise tax and broker’s commissions, which are included in “Total share repurchase costs” within this table. (b) “Purchases of treasury stock” in the Condensed Consolidated Statements of Cash Flows for the nine months ended June 30, 2024 excluded $4.0 of repurchases of common stock that were accrued in the third quarter of fiscal 2024 but did not settle until July 2024 and $1.8 of accrued excise tax that had not been paid as of June 30, 2024. “Purchases of treasury stock” in the Condensed Consolidated Statements of Cash Flows for the nine months ended June 30, 2023 excluded $8.1 of repurchases of common stock that were accrued in the third quarter of fiscal 2023 but did not settle until July 2023.

Segments (Tables)

Segments (Tables)	9 Months Ended
	Jun. 30, 2024
Segment Reporting [Abstract]
Segment Reporting Information, by Segment and Disaggregated Revenue	Three Months Ended Nine Months Ended 2024 2023 2024 2023 Net Sales Post Consumer Brands $ 1,008.1 $ 871.3 $ 3,062.2 $ 2,025.1 Weetabix 136.1 134.2 403.2 377.2 Foodservice 589.1 622.7 1,711.0 1,856.4 Refrigerated Retail 214.4 230.7 735.7 786.4 Eliminations and Corporate — 0.5 0.5 0.5 Total $ 1,947.7 $ 1,859.4 $ 5,912.6 $ 5,045.6 Segment Profit Post Consumer Brands $ 128.6 $ 83.0 $ 401.0 $ 237.8 Weetabix 24.1 17.9 63.2 58.8 Foodservice 89.6 107.7 229.8 264.9 Refrigerated Retail 5.1 18.0 63.1 57.2 Total segment profit 247.4 226.6 757.1 618.7 General corporate expenses and other 41.9 52.3 145.9 139.9 Interest expense, net 78.8 72.7 236.9 202.4 Gain on extinguishment of debt, net (1.8) (6.4) (4.6) (21.2) (Income) expense on swaps, net (3.1) (17.1) 4.7 (20.4) Earnings before income taxes and equity method loss $ 131.6 $ 125.1 $ 374.2 $ 318.0 Net sales by product Cereal $ 677.5 $ 700.8 $ 2,039.3 $ 2,028.5 Eggs and egg products 542.2 591.1 1,582.0 1,769.2 Pet food 428.9 275.3 1,316.2 275.3 Side dishes (including potato products) 174.8 171.0 576.6 561.0 Cheese and dairy 39.9 42.9 129.9 143.9 Sausage 34.2 35.5 123.4 127.8 Peanut butter 28.8 20.0 83.5 74.9 Protein-based products 9.8 9.4 23.3 23.6 Other 11.6 13.4 38.4 42.2 Eliminations — — — (0.8) Total $ 1,947.7 $ 1,859.4 $ 5,912.6 $ 5,045.6 Depreciation and amortization Post Consumer Brands $ 52.5 $ 44.1 $ 153.7 $ 109.2 Weetabix 10.2 9.2 29.6 26.6 Foodservice 33.0 31.8 98.8 95.5 Refrigerated Retail 17.9 19.1 53.5 57.4 Total segment depreciation and amortization 113.6 104.2 335.6 288.7 Corporate 7.1 2.3 17.1 4.6 Total $ 120.7 $ 106.5 $ 352.7 $ 293.3 Assets June 30, September 30, 2023 Post Consumer Brands $ 4,992.0 $ 4,782.2 Weetabix 1,831.1 1,737.8 Foodservice and Refrigerated Retail 4,867.1 4,921.6 Corporate 438.3 205.1 Total assets $ 12,128.5 $ 11,646.7

PHPC (Details)

PHPC (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	8 Months Ended	9 Months Ended		12 Months Ended
	Jun. 30, 2023	May 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2021	Mar. 31, 2023	Sep. 30, 2022
Schedule of Equity Method Investments
Investments held in trust		$ 353.4
Redeemable noncontrolling interest		312.5
Redemption of Post Holdings Partnering Corporation Series A common stock			$ 0	$ 312.5
Maximum interest to pay dissolution expenses							$ 0.1
Gain on write-off of underwriting commissions		$ 10.7
Return of subsidiary investments held in trust account			$ 0	345
Initial public offering costs					$ 17.9
Deferred Offering Costs							$ 10.7
Series A common stock included in each unit							1
PHPC Units
Schedule of Equity Method Investments
Common Unit, Issued					34,500,000
Share Price							$ 10
Redemption Price		$ 10.24
PHPC Warrants
Schedule of Equity Method Investments
Class of Warrant or Right, Exercise Price of Warrants or Rights							11.50
PHPC Private Placement Units
Schedule of Equity Method Investments
Share Price							$ 10
PHPC Sponsor | PHPC Private Placement Units
Schedule of Equity Method Investments
Common Unit, Issued					1,100,000
PHPC | PHPC Units
Schedule of Equity Method Investments
Proceeds from initial public offering					$ 345
PHPC | PHPC Private Placement Units
Schedule of Equity Method Investments
Proceeds from Issuance of Private Placement					$ 10.9
PHPC | Post Holdings, Inc.
Schedule of Equity Method Investments
Noncontrolling Interest, Ownership Percentage by Parent		31%
PHPC | Public Shareholders
Schedule of Equity Method Investments
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		69%
PHPC Sponsor | Series F Common Stock
Schedule of Equity Method Investments
Common Stock, Shares, Outstanding							8,600,000
PHPC Sponsor | PHPC Units
Schedule of Equity Method Investments
Common Unit, Issued		4,000,000			4,000,000
Return of subsidiary investments held in trust account		$ 40.9
Redeemable Noncontrolling Interest
Schedule of Equity Method Investments
Net earnings attributable to redeemable noncontrolling interest	$ 9.3			12.1
Noncontrolling interest, Redemption value adjustment	(1.9)			(5.9)
Redeemable noncontrolling interest	0			0		$ 310.6	$ 306.6
Redemption of Post Holdings Partnering Corporation Series A common stock	(312.5)			(312.5)
Noncontrolling Interest, Change in Redemption Value	$ 7.4			$ 6.2

8th Ave (Details)

8th Ave (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2023	Sep. 30, 2022
Schedule of Equity Method Investments
Net Sales	$ 1,947.7	$ 1,859.4	$ 5,912.6	$ 5,045.6
Accounts payable	392.6		392.6		$ 368.8
Other liabilities	271.8		271.8		276.7
8th Avenue
Schedule of Equity Method Investments
Net Sales	1.5	1.2	5.3	6.7
Purchases from and Royalties paid to Related Party	21.5	$ 16.8	61.1	$ 65.2
Accounts Payable | 8th Avenue
Schedule of Equity Method Investments
Accounts payable	15.6		15.6		13.3
Other Assets | 8th Avenue
Schedule of Equity Method Investments
Accounts Receivable, after Allowance for Credit Loss, Noncurrent	12.9		12.9		12.9
Other Liabilities | 8th Avenue
Schedule of Equity Method Investments
Other liabilities	$ 0.7		$ 0.7		0.7
8th Avenue
Schedule of Equity Method Investments
Equity Method Investment, Ownership Percentage	60.50%		60.50%
8th Avenue | Equity Method Investments
Schedule of Equity Method Investments
Equity method investments	$ 0		$ 0		$ 0	$ 0

WBX East Africa and Alpen (Deta

WBX East Africa and Alpen (Details) - USD ($) $ in Millions	Jun. 30, 2024	Sep. 30, 2023
Schedule of Equity Method Investments
Other assets	$ 366.9	$ 360
Alpen Food Company South Africa (Pty) Limited
Schedule of Equity Method Investments
Equity Method Investment, Ownership Percentage	50%
Alpen Food Company South Africa (Pty) Limited | Equity Method Investments
Schedule of Equity Method Investments
Other assets	$ 3.7	$ 3.6
Post Holdings, Inc. | Weetabix East Africa Limited
Schedule of Equity Method Investments
Noncontrolling Interest, Ownership Percentage by Parent	50.10%

Business Combinations (Details)

Business Combinations (Details) £ in Millions, shares in Millions, $ in Millions				3 Months Ended		9 Months Ended
	Dec. 01, 2023 USD ($)	Dec. 01, 2023 GBP (£)	Apr. 28, 2023 USD ($) shares	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)
Business Acquisition
Net Sales				$ 1,947.7	$ 1,859.4	$ 5,912.6	$ 5,045.6
Goodwill				4,648.7		4,648.7		$ 4,574.4
Selling, general and administrative expenses				324.5	300.9	988.7	768.9
Pet Food
Business Acquisition
Payments to Acquire Businesses, Base Purchase Price			$ 700
Payment at closing			715.5
Fair value of total consideration transferred			1,207.5
Issuance of common stock			$ 492.3
Pet Food | TSA Agreement
Business Acquisition
Selling, general and administrative expenses				3.5	$ 4	13	$ 4
Receivables, net				39.1		39.1		$ 35.5
Pet Food | Smucker | Common Stock
Business Acquisition
Stock Issued During Period, Shares, Acquisitions | shares			5.4
Perfection
Business Acquisition
Payments to Acquire Businesses, Base Purchase Price	$ 235
Payment at closing	238.8
Business Combination, Cash Received Related to WC Adjustment				4.6		4.6
Net Sales				62.1		146.7
Segment Profit (Loss)				4.2		9.1
Cash and cash equivalents				0.3		0.3
Receivables, net				40.8		40.8
Inventories				21.1		21.1
Prepaid expenses and other current assets				0.4		0.4
Property, net				69.9		69.9
Other intangible assets, net				81		81
Other assets				2.9		2.9
Accounts payable				(21.5)		(21.5)
Other current liabilities				(1.6)		(1.6)
Other liabilities				(1.8)		(1.8)
Total identifiable net assets				191.5		191.5
Goodwill				42.7		42.7
Fair value of total consideration transferred				234.2		$ 234.2
Perfection | Customer Relationships
Business Acquisition
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life						16 years
Other intangible assets, net				81		$ 81
Deeside
Business Acquisition
Payments to Acquire Businesses, Base Purchase Price	14.3
Net Sales				7.5		17
Segment Profit (Loss)				(0.3)		(1.2)
Fair value of total consideration transferred	20.5
Business Combination, Bargain Purchase, Gain Recognized, Amount						$ (5.8)
Business Combination, Bargain Purchase, Gain, Statement of Income or Comprehensive Income [Extensible Enumeration]						Other Operating Income (Expense), Net
Business Combination Bargain Purchase Adjustment to Gain Recognized Amount				$ 0.4
Business Combination, Bargain Purchase, Initial Gain Recognized, Amount	$ 6.2
Deeside | Euro Member Countries, Euro
Business Acquisition
Payments to Acquire Businesses, Base Purchase Price | £		£ 11.3

Business Combinations Pro Forma

Business Combinations Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Business Combinations [Abstract]
Pro forma net sales	$ 1,947.7	$ 2,058.8	$ 5,953.5	$ 6,146.2
Pro forma net earnings	$ 103.5	$ 121.4	$ 296.1	$ 284.9
Pro forma basic earnings per common share	$ 1.73	$ 1.95	$ 4.90	$ 4.63
Pro forma diluted earnings per common share	$ 1.58	$ 1.80	$ 4.52	$ 4.29

Restructuring (Details)

Restructuring (Details) - Lancaster Facility $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2024 USD ($)
Restructuring Reserve
Balance, Beginning of Period		$ 0
(Adjustment) charge to expense	$ (1.1)	6.6
Cash payments		(0.2)
Non-cash charges		0
Balance, End of Period	6.4	6.4
Total expected restructuring charges	6.7	6.7
Cumulative restructuring charges incurred to date	6.6	6.6
Remaining expected restructuring charges	$ 0.1	$ 0.1

Earnings (Loss) Per Share (Deta

Earnings (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Earnings (Loss) Per Share, Diluted, by Common Class, Including Two Class Method
Net Earnings	$ 99.8	$ 89.6	$ 285.1	$ 235.6
Impact of redeemable NCI	0	1.9	0	11
Net (loss) earnings for basic (loss) earnings per share	99.8	91.5	285.1	246.6
Impact of interest expense, net of tax, related to convertible senior notes	2.7	2.7	8.1	8.1
Net (loss) earnings for diluted (loss) earnings per share	$ 102.5	$ 94.2	$ 293.2	$ 254.7
Weighted-average shares for basic earnings per share	60	61.6	60.4	59.7
Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities	5.4	5.4	5.4	5.4
Weighted Average Number of Shares Outstanding, Diluted, Adjustment	7	6.9	6.9	7
Weighted-average shares for diluted earnings per share	67	68.5	67.3	66.7
Basic earnings per share (in usd per share)	$ 1.66	$ 1.49	$ 4.72	$ 4.13
Diluted earnings per share (in usd per share)	$ 1.53	$ 1.38	$ 4.36	$ 3.82
Stock Options
Earnings (Loss) Per Share, Diluted, by Common Class, Including Two Class Method
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	0.2	0.3	0.3	0.4
Restricted Stock Awards
Earnings (Loss) Per Share, Diluted, by Common Class, Including Two Class Method
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	0.4	0.4	0.4	0.5
Market-based performance shares
Earnings (Loss) Per Share, Diluted, by Common Class, Including Two Class Method
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	0.9	0.7	0.7	0.6
Earnings-based performance shares
Earnings (Loss) Per Share, Diluted, by Common Class, Including Two Class Method
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	0.1	0.1	0.1	0.1

Earnings (Loss) Per Share Antid

Earnings (Loss) Per Share Antidilutive shares excluded from earnings per share (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Restricted Stock Awards
Antidilutive Securities Excluded from Computation of Earnings (Loss) Per Share
Antidilutive Securities Excluded from Computation of (Loss) Earnings Per Share, Amount	0	0	0	0.1
Market-based performance shares
Antidilutive Securities Excluded from Computation of Earnings (Loss) Per Share
Antidilutive Securities Excluded from Computation of (Loss) Earnings Per Share, Amount	0	0.1	0	0.1

Inventories (Details)

Inventories (Details) - USD ($) $ in Millions	Jun. 30, 2024	Sep. 30, 2023
Inventory [Abstract]
Raw materials and supplies	$ 143.8	$ 155.9
Work in process	25.4	24.4
Finished products	591.2	573.6
Flocks	34.6	36
Inventories	$ 795	$ 789.9

Property, net (Details)

Property, net (Details) - USD ($) $ in Millions	Jun. 30, 2024	Sep. 30, 2023
Property, Plant and Equipment [Abstract]
Property, at cost	$ 4,134.8	$ 3,769.4
Accumulated depreciation	(1,947.1)	(1,748)
Property, net	$ 2,187.7	$ 2,021.4

Goodwill (Details)

Goodwill (Details) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2024	Sep. 30, 2023
Goodwill
Goodwill (gross)	$ 5,348.7	$ 5,274.4
Accumulated impairment losses	(700)	(700)
Goodwill	4,648.7	4,574.4
Goodwill from acquisition	42.7
Currency translation adjustment	31.6
Post Consumer Brands
Goodwill
Goodwill (gross)	2,303.8	2,261.1
Accumulated impairment losses	(609.1)	(609.1)
Goodwill	1,694.7	1,652
Goodwill from acquisition	42.7
Currency translation adjustment	0
Weetabix
Goodwill
Goodwill (gross)	885.9	854.3
Accumulated impairment losses	0	0
Goodwill	885.9	854.3
Goodwill from acquisition	0
Currency translation adjustment	31.6
Foodservice
Goodwill
Goodwill (gross)	1,355.3	1,355.3
Accumulated impairment losses	0	0
Goodwill	1,355.3	1,355.3
Goodwill from acquisition	0
Currency translation adjustment	0
Refrigerated Retail
Goodwill
Goodwill (gross)	803.7	803.7
Accumulated impairment losses	(90.9)	(90.9)
Goodwill	712.8	$ 712.8
Goodwill from acquisition	0
Currency translation adjustment	$ 0

Intangible Assets, net (Details

Intangible Assets, net (Details) - USD ($) $ in Millions	Jun. 30, 2024	Sep. 30, 2023
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets, Gross	$ 3,509	$ 3,421.3
Finite-Lived Intangible Assets, Accumulated Amortization	(1,382)	(1,242)
Finite-Lived Intangible Assets, Net	2,127	2,179.3
Intangible Assets, Net (Excluding Goodwill)
Carrying amount, total	4,551	4,454.4
Other intangible assets, net	3,169	3,212.4
Trademarks and brands
Indefinite-Lived Intangible Assets (Excluding Goodwill)
Carrying amount	1,042	1,033.1
Customer Relationships
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets, Gross	2,622.9	2,535.5
Finite-Lived Intangible Assets, Accumulated Amortization	(1,045.8)	(940.7)
Finite-Lived Intangible Assets, Net	1,577.1	1,594.8
Trademarks and brands
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets, Gross	886.1	885.8
Finite-Lived Intangible Assets, Accumulated Amortization	(336.2)	(301.3)
Finite-Lived Intangible Assets, Net	$ 549.9	$ 584.5

Derivative Financial Instrume_3

Derivative Financial Instruments and Hedging (Details) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2023
Derivatives, Fair Value
Financing portion of cash paid for rate-lock interest rate swaps	$ 0	$ 43.5
Commodity and energy contracts | Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value
Notional Amount of Derivative	200.8		$ 263.9
Foreign Exchange Contract - Forward Contracts | Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value
Notional Amount of Derivative	3.7		3
Interest Rate Swap | Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value
Derivative, Notional amount of terminated contracts	400	200
Derivative, Cash Received for Termination	5.2	6.7
Notional Amount of Derivative	300		700
Interest rate swap, rate lock swaps | Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value
Derivative, Cash Settlements paid, net		55.1
Derivative, Notional amount of terminated contracts		849.3
Interest rate swap, options | Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value
Derivative, Cash Settlements paid, net		2.1
Derivative, Notional amount of terminated contracts		$ 332.6
Other Current Assets | Commodity and energy contracts
Derivatives, Fair Value
Derivative Asset, Fair Value, Gross Asset	2.9		3.7
Other Current Assets | Foreign Exchange Contract - Forward Contracts
Derivatives, Fair Value
Derivative Asset, Fair Value, Gross Asset	0.1		0
Other Current Assets | Interest Rate Swap
Derivatives, Fair Value
Derivative Asset, Fair Value, Gross Asset	3.6		10.6
Other Assets | Commodity and energy contracts
Derivatives, Fair Value
Derivative Asset, Fair Value, Gross Asset	2.1		0
Other Assets | Interest Rate Swap
Derivatives, Fair Value
Derivative Asset, Fair Value, Gross Asset	2.4		11.3
Assets, Total
Derivatives, Fair Value
Derivative Asset, Fair Value, Gross Asset	11.1		25.6
Other Current Liabilities | Commodity and energy contracts
Derivatives, Fair Value
Derivative Liability, Fair Value, Gross Liability	9.7		16.1
Liabilities, Total
Derivatives, Fair Value
Derivative Liability, Fair Value, Gross Liability	$ 9.7		$ 16.1

Derivative Financial Instrume_4

Derivative Financial Instruments and Hedging (Gain) Loss recognized in Statement of Operations from derivative instruments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Commodity and energy contracts
Derivative Instruments, (Gain) Loss
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Cost of goods sold	Cost of goods sold	Cost of goods sold	Cost of goods sold
Foreign Exchange Contract - Forward Contracts
Derivative Instruments, (Gain) Loss
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Selling, general and administrative expenses	Selling, general and administrative expenses	Selling, general and administrative expenses	Selling, general and administrative expenses
PHPC Warrants
Derivative Instruments, (Gain) Loss
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Derivatives Not Designated as Hedging Instruments | Commodity and energy contracts
Derivative Instruments, (Gain) Loss
(Gain) Loss Recognized in Statement of Operations	$ 5.6	$ 15.8	$ 30.5	$ 30.1
Derivatives Not Designated as Hedging Instruments | Foreign Exchange Contract - Forward Contracts
Derivative Instruments, (Gain) Loss
(Gain) Loss Recognized in Statement of Operations	0	0.1	0	0.1
Derivatives Not Designated as Hedging Instruments | Interest Rate Swap
Derivative Instruments, (Gain) Loss
(Gain) Loss Recognized in Statement of Operations	(3.1)	(17.1)	4.7	(20.4)
Derivatives Not Designated as Hedging Instruments | PHPC Warrants
Derivative Instruments, (Gain) Loss
(Gain) Loss Recognized in Statement of Operations	$ 0	$ (1.5)	$ 0	$ (1)

Derivative Financial Instrume_5

Derivative Financial Instruments and Hedging Derivatives designated as hedges and pledged collateral (Details) - USD ($) $ in Millions	Jun. 30, 2024	Sep. 30, 2023
Derivative Instruments, (Gain) Loss
Collateral Already Posted	$ 9.3	$ 23.4

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Millions	Jun. 30, 2024	Sep. 30, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Deferred Compensation Investment	$ 15.5	$ 13
Derivative Asset	11.1	25.6
Assets, Fair Value Disclosure	26.6	38.6
Deferred Compensation Liabilities	45.4	36.8
Derivative Liability	9.7	16.1
Other Liabilities, Fair Value Disclosure	55.1	52.9
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Deferred Compensation Investment	15.5	13
Derivative Asset	0	0
Assets, Fair Value Disclosure	15.5	13
Deferred Compensation Liabilities	0	0
Derivative Liability	0	0
Other Liabilities, Fair Value Disclosure	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Deferred Compensation Investment	0	0
Derivative Asset	11.1	25.6
Assets, Fair Value Disclosure	11.1	25.6
Deferred Compensation Liabilities	45.4	36.8
Derivative Liability	9.7	16.1
Other Liabilities, Fair Value Disclosure	55.1	52.9
Debt, Fair Value	5,904.7	5,491.5
Level 2 | 2.50% convertible senior notes | Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt, Fair Value	$ 632.8	$ 572.6

Long-Term Debt (Details)

Long-Term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2024	Sep. 30, 2023	Aug. 12, 2022
Debt Instrument
Long-term Debt, Including Current Maturities	$ 6,420.1	$ 6,049.6
Current portion of long-term debt	1.2	1.1
Unamortized Debt Issuance Costs, net	45.6	42
Plus: Unamortized premium and discount, net	24.5	32.5
Total Long-term Debt	6,397.8	6,039
Municipal Bonds
Debt Instrument
Long-term Debt	4.2	5.3
Term Loan
Debt Instrument
Long-term Debt	0	400
Revolving Credit Facility
Debt Instrument
Long-term Debt	300	0
2.50% convertible senior notes | Senior Notes
Debt Instrument
Long-term Debt	$ 575	575	$ 575
Debt Instrument, Interest Rate, Stated Percentage	2.50%
4.50% Senior Notes Maturing in September 2031 | Senior Notes
Debt Instrument
Long-term Debt	$ 980.6	1,049.7
4.625% Senior Notes Maturing April 2030 | Senior Notes
Debt Instrument
Long-term Debt	1,385.4	1,385.4
5.50% Senior Notes Maturing in December 2029 | Senior Notes
Debt Instrument
Long-term Debt	1,235	1,235
5.625% senior notes maturing January 2028 | Senior Notes
Debt Instrument
Long-term Debt	939.9	939.9
5.75% Senior Notes Maturing March 2027 | Senior Notes
Debt Instrument
Long-term Debt	0	459.3
6.25% Senior Notes Maturing in February 2032 | Senior Notes
Debt Instrument
Long-term Debt	$ 1,000	$ 0
Debt Instrument, Interest Rate, Stated Percentage	6.25%

Long-Term Debt - Senior Notes (

Long-Term Debt - Senior Notes (Details)	9 Months Ended
	Jun. 30, 2024 USD ($) d $ / shares	Jun. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Aug. 12, 2022 USD ($)
Debt Instrument
Payments of debt issuance costs and deferred financing fees	$ 19,900,000	$ 3,100,000
6.25% Senior Notes Maturing in February 2032 | Senior Notes
Debt Instrument
Long-term Debt	$ 1,000,000,000		$ 0
Debt Instrument, Interest Rate, Stated Percentage	6.25%
Proceeds from Issuance of Debt	$ 986,700,000
Payments of debt issuance costs and deferred financing fees	13,300,000
2.50% convertible senior notes | Senior Notes
Debt Instrument
Long-term Debt	$ 575,000,000		$ 575,000,000	$ 575,000,000
Debt Instrument, Interest Rate, Stated Percentage	2.50%
Debt Instrument, Convertible, Conversion Ratio	9.4248
Debt Instrument, Convertible, Conversion Price | $ / shares	$ 106.10
Debt Instrument, Convertible, Threshold Consecutive Trading Days | d	5
Debt Instrument, Convertible, Threshold Trading Days | d	10
Debt Instrument, Issued, Principal	$ 1,000
Debt Instrument, Convertible, Latest Date	Aug. 15, 2027
Debt Instrument, Convertible, Earliest Date	May 15, 2027
2.50% convertible senior notes | Senior Notes | Maximum
Debt Instrument
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger	130%
2.50% convertible senior notes | Senior Notes | Minimum
Debt Instrument
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger	98%

Long-Term Debt - Credit Agreeme

Long-Term Debt - Credit Agreement (Details) $ in Millions	9 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)
Debt Instrument
Payments of debt issuance costs and deferred financing fees	$ 19.9	$ 3.1
Debt Covenant, Leverage Ratio	4.25
Revolving Credit Facility
Debt Instrument
Line of Credit Facility, Current Borrowing Capacity	$ 1,000		$ 750
Payments of debt issuance costs and deferred financing fees	6.6
Proceeds from Lines of Credit	645	0
Repayments of Lines of Credit	345	$ 0
Letters of Credit Outstanding, Amount	20		19.7
Line of Credit Facility, Remaining Borrowing Capacity	680		730.3
Long-term Debt	$ 300		0
Line of Credit Facility, Interest Rate at Period End	6.93%
Debt Covenant, Maximum Undischarged Judgments	$ 125
Revolving Credit Facility | High-End Ratio
Debt Instrument
Debt Covenant, Leverage Ratio	3
Revolving Credit Facility | Low-End Ratio
Debt Instrument
Debt Covenant, Leverage Ratio	1.50
Revolving Credit Facility | Maximum
Debt Instrument
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.375%
Revolving Credit Facility | Minimum
Debt Instrument
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.25%
Revolving Credit Facility | NYFRB
Debt Instrument
Debt Instrument, Basis Spread on Variable Rate	0.50%
Revolving Credit Facility | Base Rate | Maximum
Debt Instrument
Debt Instrument, Basis Spread on Variable Rate	1%
Revolving Credit Facility | Base Rate | Median
Debt Instrument
Debt Instrument, Basis Spread on Variable Rate	0.75%
Revolving Credit Facility | Base Rate | Minimum
Debt Instrument
Debt Instrument, Basis Spread on Variable Rate	0.50%
Revolving Credit Facility | One-Month adjusted term SOFR
Debt Instrument
Debt Instrument, Basis Spread on Variable Rate	1%
Revolving Credit Facility | Adjusted term SOFR | Maximum
Debt Instrument
Debt Instrument, Basis Spread on Variable Rate	2%
Revolving Credit Facility | Adjusted term SOFR | Median
Debt Instrument
Debt Instrument, Basis Spread on Variable Rate	1.75%
Revolving Credit Facility | Adjusted term SOFR | Minimum
Debt Instrument
Debt Instrument, Basis Spread on Variable Rate	1.50%
Line of Credit
Debt Instrument
Line of Credit Facility, Current Borrowing Capacity	$ 75		$ 75

Long-Term Debt - Third Incremen

Long-Term Debt - Third Incremental Term Loan (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Nov. 18, 2022
Debt Instrument
Gross Exchanges of Long-term debt	$ 0	$ 0	$ 0	$ 99.9
Gross Repayments of Long-term debt	$ 18	$ 50	$ 1,274.5	201.7
Third Incremental Term Loan | Term Loan
Debt Instrument
Loans Payable to Bank					$ 130
Gross Exchanges of Long-term debt				99.9
Gross Repayments of Long-term debt				$ 30.1

Long-Term Debt - Fourth Increme

Long-Term Debt - Fourth Incremental Term Loan (Details) - Fourth Incremental Term Loan - Term Loan - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Apr. 26, 2023
Extinguishment of Debt [Line Items]
Loans Payable to Bank		$ 400
Debt Instrument, Interest Rate, Effective Percentage	7.67%
Base Rate
Extinguishment of Debt [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.25%
Secured Overnight Financing Rate
Extinguishment of Debt [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.25%

Long-Term Debt - Repayments (De

Long-Term Debt - Repayments (Details) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)
Debt Disclosure [Abstract]
Debt Covenant, Leverage Ratio	4.25		4.25
Debt Covenant, Percentage of Revolving Credit Commitments	30%		30%
Extinguishment of Debt [Line Items]
Gross Repayments of Long-term debt	$ 18	$ 50	$ 1,274.5	$ 201.7
Gross Exchanges of Long-term debt	$ 0	0	$ 0	99.9
Debt Covenant, Leverage Ratio	4.25		4.25
Debt Covenant, Percentage of Revolving Credit Commitments	30%		30%
Loss on extinguishment of debt and refinancing fees, net
Extinguishment of Debt [Line Items]
Payment (Proceeds) for debt discounts and premiums	$ (1.9)	(6.4)	$ (3.5)	(23.3)
Write off of Debt Issuance Costs and Deferred Financing Fees	0.1	0.3	3.5	2.4
Write-off of Unamortized Debt Discount/(Premium)	0	(0.3)	(4.6)	(0.3)
Municipal Bonds
Extinguishment of Debt [Line Items]
Gross Repayments of Long-term debt			1.1	1.1
Gross Exchanges of Long-term debt			0	0
Municipal Bonds | Loss on extinguishment of debt and refinancing fees, net
Extinguishment of Debt [Line Items]
Payment (Proceeds) for debt discounts and premiums			0	0
Write off of Debt Issuance Costs and Deferred Financing Fees			0	0
Write-off of Unamortized Debt Discount/(Premium)			0	0
Revolving Credit Facility
Extinguishment of Debt [Line Items]
Gross Repayments of Long-term debt			345
Gross Exchanges of Long-term debt			0
Revolving Credit Facility | Loss on extinguishment of debt and refinancing fees, net
Extinguishment of Debt [Line Items]
Payment (Proceeds) for debt discounts and premiums			0
Write off of Debt Issuance Costs and Deferred Financing Fees			0
Write-off of Unamortized Debt Discount/(Premium)			0
4.50% Senior Notes Maturing in September 2031 | Senior Notes
Extinguishment of Debt [Line Items]
Gross Repayments of Long-term debt	18	20.7	69.1	141.2
Gross Exchanges of Long-term debt	0	0	0	0
4.50% Senior Notes Maturing in September 2031 | Senior Notes | Loss on extinguishment of debt and refinancing fees, net
Extinguishment of Debt [Line Items]
Payment (Proceeds) for debt discounts and premiums	(1.9)	(3)	(7.9)	(19.9)
Write off of Debt Issuance Costs and Deferred Financing Fees	0.1	0.1	0.5	1.1
Write-off of Unamortized Debt Discount/(Premium)	$ 0	0	0	0
4.625% Senior Notes Maturing April 2030 | Senior Notes
Extinguishment of Debt [Line Items]
Gross Repayments of Long-term debt		29.3		29.3
Gross Exchanges of Long-term debt		0		0
4.625% Senior Notes Maturing April 2030 | Senior Notes | Loss on extinguishment of debt and refinancing fees, net
Extinguishment of Debt [Line Items]
Payment (Proceeds) for debt discounts and premiums		(3.4)		(3.4)
Write off of Debt Issuance Costs and Deferred Financing Fees		0.2		0.2
Write-off of Unamortized Debt Discount/(Premium)		$ (0.3)		(0.3)
5.75% Senior Notes Maturing March 2027 | Senior Notes
Extinguishment of Debt [Line Items]
Gross Repayments of Long-term debt			459.3
Gross Exchanges of Long-term debt			0
5.75% Senior Notes Maturing March 2027 | Senior Notes | Loss on extinguishment of debt and refinancing fees, net
Extinguishment of Debt [Line Items]
Payment (Proceeds) for debt discounts and premiums			4.4
Write off of Debt Issuance Costs and Deferred Financing Fees			1.6
Write-off of Unamortized Debt Discount/(Premium)			(4.6)
Fourth Incremental Term Loan | Term Loan
Extinguishment of Debt [Line Items]
Gross Repayments of Long-term debt			400
Gross Exchanges of Long-term debt			0
Fourth Incremental Term Loan | Term Loan | Loss on extinguishment of debt and refinancing fees, net
Extinguishment of Debt [Line Items]
Payment (Proceeds) for debt discounts and premiums			0
Write off of Debt Issuance Costs and Deferred Financing Fees			1.4
Write-off of Unamortized Debt Discount/(Premium)			$ 0
Third Incremental Term Loan | Term Loan
Extinguishment of Debt [Line Items]
Gross Repayments of Long-term debt				30.1
Gross Exchanges of Long-term debt				99.9
Third Incremental Term Loan | Term Loan | Loss on extinguishment of debt and refinancing fees, net
Extinguishment of Debt [Line Items]
Payment (Proceeds) for debt discounts and premiums				0
Write off of Debt Issuance Costs and Deferred Financing Fees				1.1
Write-off of Unamortized Debt Discount/(Premium)				$ 0

Pension and Other Postretirem_3

Pension and Other Postretirement Benefits - Components of Net Periodic Benefit Cost (Gain) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Defined Benefit Plan Disclosure
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax	$ 0	$ 0	$ 8.3	$ 0
Pension Benefits | North America
Components of net periodic benefit cost (gain)
Service cost	0.7	0.6	1.7	1.7
Interest cost	1.5	1.3	4.3	3.9
Expected return on plan assets	(2)	(1.9)	(6.1)	(5.7)
Recognized net actuarial loss (gain)	(0.1)	0	(0.3)	(0.1)
Recognized prior service cost (credit)	0.3	0	0.4	0.1
Net periodic benefit cost (income)	0.4	0	0	(0.1)
Pension Benefits | Other International
Components of net periodic benefit cost (gain)
Service cost	0.1	0	0.2	0
Interest cost	6.5	6	19.2	17.3
Expected return on plan assets	(8.8)	(7.9)	(26)	(22.9)
Recognized net actuarial loss (gain)	0	0	0.1	0.1
Recognized prior service cost (credit)	0.1	0.1	0.3	0.3
Net periodic benefit cost (income)	(2.1)	(1.8)	(6.2)	(5.2)
Other Postretirement Benefit Plan | North America
Components of net periodic benefit cost (gain)
Service cost	0.1	0.1	0.2	0.2
Interest cost	0.7	0.6	2	1.9
Recognized net actuarial loss (gain)	(0.3)	(0.1)	(0.8)	(0.4)
Recognized prior service cost (credit)	(0.2)	(1.2)	(0.5)	(3.5)
Net periodic benefit cost (income)	$ 0.3	$ (0.6)	$ 0.9	$ (1.8)

Shareholders' Equity (Details)

Shareholders' Equity (Details) - USD ($) $ / shares in Units, shares in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Equity, Class of Treasury Stock [Line Items]
Purchased call option strike price for share repurchase contracts	0		0
Written Call Option Strike Price for share repurchase contracts	99.45		99.45
Payment for share repurchase contracts			$ (50,000,000)	$ 0
Share repurchase contracts - number of shares received	0.5		0.5
Proceeds from share repurchase contracts			$ 50,900,000	$ 0
Common Stock
Equity, Class of Treasury Stock [Line Items]
Shares repurchased	2	1.9	2.5	2.9
Average price per share (a)	$ 104.18	$ 86.64	$ 100.71	$ 86.91
Total Share Repurchase Cost	$ 209,700,000	$ 166,800,000	$ 254,500,000	$ 250,500,000
Sales and Excise Tax Payable, Current	$ 1,800,000		1,800,000
Accrued repurchases of common stock			$ 4,000,000	$ 8,100,000

Segments (Details)

Segments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2023
Segment Reporting Information
Net Sales	$ 1,947.7	$ 1,859.4	$ 5,912.6	$ 5,045.6
Interest expense, net	78.8	72.7	236.9	202.4
Gain on extinguishment of debt, net	(1.8)	(6.4)	(4.6)	(21.2)
(Income) expense on swaps, net	(3.1)	(17.1)	4.7	(20.4)
Earnings before income taxes and equity method loss	131.6	125.1	374.2	318
Depreciation and amortization	120.7	106.5	352.7	293.3
Assets	12,128.5		12,128.5		$ 11,646.7
Operating Segments
Segment Reporting Information
Net Sales	1,947.7	1,859.4	5,912.6	5,045.6
Segment Profit (Loss)	247.4	226.6	757.1	618.7
Depreciation and amortization	113.6	104.2	335.6	288.7
Operating Segments | Post Consumer Brands
Segment Reporting Information
Net Sales	1,008.1	871.3	3,062.2	2,025.1
Segment Profit (Loss)	128.6	83	401	237.8
Depreciation and amortization	52.5	44.1	153.7	109.2
Assets	4,992		4,992		4,782.2
Operating Segments | Weetabix
Segment Reporting Information
Net Sales	136.1	134.2	403.2	377.2
Segment Profit (Loss)	24.1	17.9	63.2	58.8
Depreciation and amortization	10.2	9.2	29.6	26.6
Assets	1,831.1		1,831.1		1,737.8
Operating Segments | Foodservice
Segment Reporting Information
Net Sales	589.1	622.7	1,711	1,856.4
Segment Profit (Loss)	89.6	107.7	229.8	264.9
Depreciation and amortization	33	31.8	98.8	95.5
Operating Segments | Refrigerated Retail
Segment Reporting Information
Net Sales	214.4	230.7	735.7	786.4
Segment Profit (Loss)	5.1	18	63.1	57.2
Depreciation and amortization	17.9	19.1	53.5	57.4
Operating Segments | Foodservice and Refrigerated Retail
Segment Reporting Information
Assets	4,867.1		4,867.1		4,921.6
Eliminations and Corporate
Segment Reporting Information
Net Sales	0	0.5	0.5	0.5
Corporate
Segment Reporting Information
General corporate expenses and other	41.9	52.3	145.9	139.9
Depreciation and amortization	7.1	2.3	17.1	4.6
Assets	438.3		438.3		$ 205.1
Cereal | Operating Segments
Segment Reporting Information
Net Sales	677.5	700.8	2,039.3	2,028.5
Eggs and egg products | Operating Segments
Segment Reporting Information
Net Sales	542.2	591.1	1,582	1,769.2
Side dishes (including potato products) | Operating Segments
Segment Reporting Information
Net Sales	174.8	171	576.6	561
Pet Food | Operating Segments
Segment Reporting Information
Net Sales	428.9	275.3	1,316.2	275.3
Cheese and dairy | Operating Segments
Segment Reporting Information
Net Sales	39.9	42.9	129.9	143.9
Sausage | Operating Segments
Segment Reporting Information
Net Sales	34.2	35.5	123.4	127.8
Peanut butter | Operating Segments
Segment Reporting Information
Net Sales	28.8	20	83.5	74.9
Protein-based products and supplements | Operating Segments
Segment Reporting Information
Net Sales	9.8	9.4	23.3	23.6
Other | Operating Segments
Segment Reporting Information
Net Sales	11.6	13.4	38.4	42.2
Eliminations | Eliminations and Corporate
Segment Reporting Information
Net Sales	$ 0	$ 0	$ 0	$ (0.8)