Blackrock Municipal Bond Fund NPORT-P BlackRock Impact Municipal Fund (Feb 2023 report)

Schedule of Investments (unaudited)  February 28, 2023 BlackRock Impact Municipal Fund (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Municipal Bonds
Alabama — 0.2%
Sumter County Industrial Development Authority, RB, AMT, 6.00%, 07/15/52(a)	$	100	$	87,854
Arizona — 2.2%
Arizona Industrial Development Authority, RB 5.25%, 07/01/43(b)		150		144,153
Series A, 4.00%, 02/01/50		1,000		898,170
				1,042,323
Arkansas — 2.3%
University of Arkansas, RB, Series A, 5.00%, 04/01/47		1,000		1,071,637
California — 13.0%
California Community Choice Financing Authority, RB(a)
Series A, 4.00%, 10/01/52		1,500		1,482,885
Series C, 5.25%, 01/01/54		740		770,114
California Public Finance Authority, RB, Series A, 4.00%, 07/15/51		1,000		943,082
California School Finance Authority, RB, 5.00%, 08/01/42(b)		125		125,980
California State Public Works Board, RB, Series D, 4.00%, 05/01/45		1,000		970,505
City of Los Angeles California Wastewater System Revenue, Refunding RB, Series A, Subordinate, 4.00%, 06/01/52		1,500		1,433,769
CSCDA Community Improvement Authority, RB, M/F Housing(b)
3.25%, 04/01/57		250		172,129
Series A-2, 3.00%, 02/01/57		350		232,910
				6,131,374
Colorado — 1.8%
Colorado School of Mines, RB, Series A, (AGM), 5.25%, 12/01/47		290		312,262
Denver City & County School District No. 1, GO, Series A, AMT, (SAW), 5.00%, 12/01/42		500		554,896
				867,158
Connecticut — 4.6%
State of Connecticut, GO, Series B, 5.00%, 01/15/42		1,000		1,091,144
University of Connecticut, RB, Series A, AMT, 5.00%, 05/01/39		1,000		1,095,825
				2,186,969
Delaware — 0.2%
Affordable Housing Opportunities Trust, RB, Series AH-01, Class B, 6.88%, 05/01/39(b)(c)		80		73,024
District of Columbia — 2.3%
District of Columbia, RB, Class A, AMT, 5.50%, 02/28/34		1,000		1,100,526
Florida — 5.4%
Brevard County Health Facilities Authority, Refunding RB, Series A, 4.00%, 04/01/52		1,000		891,375
County of Miami-Dade Florida Water & Sewer System Revenue, RB, 4.00%, 10/01/48		1,000		912,268
Florida Development Finance Corp., RB
Series A, 4.00%, 06/15/42		500		418,674
Series A, 5.00%, 06/15/47		375		352,800
				2,575,117

Security	Par (000)		Value
Georgia — 0.7%
Georgia Housing & Finance Authority, Refunding RB, S/F Housing, Series A, 4.00%, 06/01/49	$	325	$	331,960
Illinois — 5.5%
Chicago Board of Education, GO
Series A, 5.00%, 12/01/47		500		474,219
Series A, AMT, 5.00%, 12/01/33		500		513,470
Chicago Transit Authority Sales Tax Receipts Fund, Refunding RB, Series A, 2nd Lien, 5.00%, 12/01/57		1,200		1,227,556
Illinois Housing Development Authority, RB, S/F Housing, Series G, (FHLMC, FNMA, GNMA), 6.25%, 10/01/52		350		381,900
				2,597,145
Kentucky — 3.2%
City of Henderson Kentucky, RB, Series SE, AMT, 4.70%, 01/01/52(b)		500		469,715
Louisville/Jefferson County Metropolitan Government, RB, Series A, (AGM), 5.00%, 05/15/47		1,000		1,045,556
				1,515,271
Louisiana — 2.6%
Jefferson Parish Consolidated Sewerage District No. 1, RB, (BAM), 4.00%, 02/01/39		1,000		961,775
Louisiana Public Facilities Authority, RB, Series A, 6.38%, 06/01/52(b)		250		251,814
				1,213,589
Maine — 0.1%
Finance Authority of Maine, RB, AMT, 8.00%, 12/01/51(b)		100		62,987
Maryland — 1.5%
Maryland Economic Development Corp., RB, Class B, AMT, 5.25%, 06/30/47		715		718,654
Massachusetts — 5.5%
Massachusetts Bay Transportation Authority Assessment Revenue, Refunding RB, Series A, 5.00%, 07/01/52		1,500		1,629,079
University of Massachusetts Building Authority, RB, Series 1, 4.00%, 11/01/46		1,000		960,246
				2,589,325
Michigan — 2.9%
Ludington Area School District, GO, Series II, (BAM Q-SBLF), 4.00%, 05/01/51		1,000		930,181
Michigan Finance Authority, RB, 4.00%, 02/15/47		500		453,973
				1,384,154
Minnesota — 1.8%
Duluth Economic Development Authority, RB, Class B, 5.25%, 06/15/42		500		504,526
Minnesota Housing Finance Agency, RB, S/F Housing, Series N, (FHLMC, FNMA, GNMA), 6.00%, 01/01/53		340		368,992
				873,518
Mississippi — 0.2%
Mississippi Business Finance Corp., RB, AMT, 7.75%, 07/15/47(a)		100		100,086
New Hampshire — 1.5%
New Hampshire Business Finance Authority, RB, M/F Housing, Series 2022, 4.38%, 09/20/36		744		719,149
New Jersey — 0.3%
Camden County Improvement Authority, RB, 6.00%, 06/15/47		115		120,266

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Schedule of Investments (unaudited) (continued) February 28, 2023 BlackRock Impact Municipal Fund (Percentages shown are based on Net Assets)

Security	Par (000)		Value
New York — 14.5%
Battery Park City Authority, RB, 4.00%, 11/01/44	$	1,500	$	1,452,991
Build NYC Resource Corp., RB
5.75%, 06/01/42(b)		250		252,531
Series A, 5.00%, 07/01/32		245		228,331
Metropolitan Transportation Authority, Refunding RB, Series A-1, 5.00%, 11/15/49		1,000		987,224
New York City Housing Development Corp., RB, M/F Housing, Class F-1, 4.75%, 11/01/47		1,000		1,000,103
New York City Municipal Water Finance Authority, RB, Series CC-1, 4.00%, 06/15/52		1,000		941,996
New York Power Authority, RB
(AGM), 4.00%, 11/15/39		1,000		995,353
(AGM), 4.00%, 11/15/40		1,000		984,188
				6,842,717
North Carolina — 0.5%
North Carolina Housing Finance Agency, RB, S/F Housing, (FHLMC, FNMA, GNMA), 3.75%, 07/01/52		250		246,848
North Dakota — 0.5%
North Dakota Housing Finance Agency, RB, S/F Housing, Series A, 4.00%, 01/01/53		230		229,782
Ohio — 1.4%
Ohio State University, RB, Series B-1, VRDN, 2.66%, 12/01/39(a)		500		500,000
Southern Ohio Port Authority, RB, Series A, AMT, 7.00%, 12/01/42(b)		200		140,854
				640,854
Oregon — 1.4%
Oregon State Facilities Authority, RB, Series A, 5.00%, 06/01/52		125		128,251
State of Oregon Housing & Community Services Department, RB, S/F Housing, Series A, AMT, 4.00%, 07/01/51		535		535,398
				663,649
Pennsylvania — 5.7%
City of Philadelphia Pennsylvania Water & Wastewater Revenue, RB, Series C, 5.50%, 06/01/47		1,000		1,107,127
Pennsylvania Housing Finance Agency, Refunding RB, S/F Housing, Series 2022, 4.25%, 10/01/52		470		474,631
Southeastern Pennsylvania Transportation Authority, RB, 5.25%, 06/01/47		1,000		1,101,751
				2,683,509
Tennessee — 0.4%
Tennessee Housing Development Agency, Refunding RB, S/F Housing, Series 1, 3.75%, 07/01/52		200		197,474
Texas — 6.7%
Arlington Higher Education Finance Corp., RB (PSF), 5.00%, 08/15/47		500		529,038

Security	Par (000)		Value
Texas (continued)
Arlington Higher Education Finance Corp., RB (continued)
Series A, 5.25%, 08/15/32	$	250	$	249,913
City of El Paso Texas Water & Sewer Revenue, Refunding RB, 5.00%, 03/01/46		1,000		1,065,729
New Hope Cultural Education Facilities Finance Corp., Refunding RB, Class A, 6.63%, 10/01/43		100		96,532
Tarrant County Cultural Education Facilities Finance Corp., RB, Class F, 5.00%, 11/15/52(a)		415		456,078
Texas State Technical College, RB, (AGM), 5.50%, 08/01/42		665		747,842
				3,145,132
Utah — 3.6%
University of Utah, RB, Series A, 4.00%, 08/01/43		1,500		1,468,773
Utah Infrastructure Agency, RB, 5.00%, 10/15/32		250		257,968
				1,726,741
Virginia — 2.2%
Henrico County Economic Development Authority, RB, Class A, 5.00%, 10/01/47		1,000		1,040,306
Total Long-Term Investments — 94.7% (Cost: $47,058,866)				44,779,098
	Shares
Short-Term Securities
Money Market Funds — 3.9%
BlackRock Liquidity Funds, MuniCash, Institutional Class, 2.80%(d)(e)		1,857,565		1,857,379
Total Short-Term Securities — 3.9% (Cost: $1,857,369)				1,857,379
Total Investments — 98.6% (Cost: $48,916,235)				46,636,477
Other Assets Less Liabilities — 1.4%				642,416
Net Assets — 100.0%			$	47,278,893

^(a)  Variable rate security. Interest rate resets periodically. The rate shown is the effective interest rate as of period end. Security description also includes the reference rate and spread if published and available.

^(b)  Security exempt from registration pursuant to Rule 144A under the Securities Act of 1933, as amended. These securities may be resold in transactions exempt from registration to qualified institutional investors.

^(c)  Security is valued using significant unobservable inputs and is classified as Level 3 in the fair value hierarchy.

^(d)  Affiliate of the Fund.

^(e)  Annualized 7-day yield as of period end.

For Fund compliance purposes, the Fund’s sector classifications refer to one or more of the sector sub-classifications used by one or more widely recognized market indexes or rating group indexes, and/or as defined by the investment adviser. These definitions may not apply for purposes of this report, which may combine such sector sub-classifications for reporting ease.

SCHEDULE   OF   INVESTMENTS 2

Schedule of Investments (unaudited) (continued) February 28, 2023 BlackRock Impact Municipal Fund

Affiliates

Investments in issuers considered to be affiliate(s) of the Fund during the period ended February 28, 2023 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 05/31/22		Purchases at Cost		Proceeds from Sales			Net Realized Gain (Loss)			Change in Unrealized Appreciation (Depreciation)			Value at 02/28/23		Shares Held at 02/28/23		Income		Capital Gain Distributions from Underlying Funds
BlackRock Liquidity Funds, MuniCash, Institutional Class	$	1,983,841	$	—	$	(125,971	)(a)	$	(299	)	$	(192	)	$	1,857,379		1,857,565	$	21,473	$	—

^(a)  Represents net amount purchased (sold).

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Short Contracts
10-Year U.S. Treasury Note		23		06/21/23	$	2,568	$	3,418
U.S. Long Bond		35		06/21/23		4,390		48,495
5-Year U.S. Treasury Note		11		06/30/23		1,178		2,052
							$	53,965

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. These inputs to valuation techniques are categorized into a fair value hierarchy consisting of three broad levels for financial reporting purposes as follows:

• Level 1 — Unadjusted price quotations in active markets/exchanges for identical assets or liabilities that the Fund has the ability to access;

• Level 2 — Other observable inputs (including, but not limited to, quoted prices for similar assets or liabilities in markets that are active, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the assets or liabilities (such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks and default rates) or other market–corroborated inputs); and

• Level 3 — Unobservable inputs based on the best information available in the circumstances, to the extent observable inputs are not available (including the Valuation Committee’s assumptions used in determining the fair value of financial instruments).

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. Investments classified within Level 3 have significant unobservable inputs used by the Valuation Committee in determining the price for Fair Valued Investments. Level 3 investments include equity or debt issued by privately held companies or funds. There may not be a secondary market, and/or there are a limited number of investors. The categorization of a value determined for financial instruments is based on the pricing transparency of the financial instruments and is not necessarily an indication of the risks associated with investing in those securities. For information about the Fund’s policy regarding valuation of financial instruments, refer to its most recent financial statements.

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Schedule of Investments (unaudited) (continued) February 28, 2023 BlackRock Impact Municipal Fund

Fair Value Hierarchy as of Period End (continued)

The following table summarizes the Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Long-Term Investments
Municipal Bonds	$	—	$	44,706,074	$	73,024	$	44,779,098
Short-Term Securities
Money Market Funds		1,857,379		—		—		1,857,379
	$	1,857,379	$	44,706,074	$	73,024	$	46,636,477
Derivative Financial Instruments(a)
Assets
Interest Rate Contracts	$	53,965	$	—	$	—	$	53,965

^(a)  Derivative financial instruments are futures contracts. Futures contracts are valued at the unrealized appreciation (depreciation) on the instrument.

Portfolio Abbreviation

AGM	Assured Guaranty Municipal Corp.
AMT	Alternative Minimum Tax
BAM	Build America Mutual Assurance Co.
FHLMC	Federal Home Loan Mortgage Corp.
FNMA	Federal National Mortgage Association
GNMA	Government National Mortgage Association
GO	General Obligation Bonds
M/F	Multi-Family
PSF	Permanent School Fund
Q-SBLF	Qualified School Bond Loan Fund
RB	Revenue Bond
S/F	Single-Family
SAW	State Aid Withholding
VRDN	Variable Rate Demand Note

SCHEDULE   OF   INVESTMENTS 4