Schedule of Investments (unaudited) August 31, 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	$	71,393
Arizona — 2.1%
Arizona Industrial Development Authority, RB 5.25%, 07/01/43(b)		150		139,396
Series A, 4.00%, 02/01/50		1,000		869,463
				1,008,859
Arkansas — 2.9%
Arkansas Development Finance Authority, RB
AMT, 6.88%, 07/01/48(b)		200		204,500
AMT, 5.70%, 05/01/53		100		99,849
University of Arkansas, RB, Series A, 5.00%, 04/01/47		1,000		1,064,555
				1,368,904
California — 7.5%
California Community Choice Financing Authority, RB(a)
Series A, 4.00%, 10/01/52		1,500		1,483,083
Series C, 5.25%, 01/01/54		585		605,660
California School Finance Authority, RB, 5.00%, 08/01/42(b)		125		121,938
California State Public Works Board, RB, Series D, 4.00%, 05/01/45		1,000		966,010
CSCDA Community Improvement Authority, RB, M/F Housing(b)
3.25%, 04/01/57		250		167,160
Series A-2, 3.00%, 02/01/57		350		224,401
				3,568,252
Colorado — 1.8%
Colorado School of Mines, RB, Series A, (AGM), 5.25%, 12/01/47		290		310,248
Denver City & County School District No. 1, GO, Series A, AMT, (SAW), 5.00%, 12/01/42		500		543,852
				854,100
Connecticut — 5.0%
Connecticut State Health & Educational Facilities Authority, RB, 5.25%, 07/15/48		180		193,014
State of Connecticut, GO, Series B, 5.00%, 01/15/42		1,000		1,089,051
University of Connecticut, RB, Series A, AMT, 5.00%, 05/01/39		1,000		1,089,292
				2,371,357
Delaware — 0.1%
Affordable Housing Opportunities Trust, RB, Series AH-01, Class B, 6.88%, 05/01/39(b)(c)		80		70,086
District of Columbia — 2.9%
District of Columbia, RB, Class A, AMT, 5.50%, 02/28/34		1,000		1,124,738
Washington Metropolitan Area Transit Authority Dedicated Revenue, RB, Series A, 4.13%, 07/15/47		250		236,184
				1,360,922
Florida — 8.9%
Brevard County Health Facilities Authority, Refunding RB, Series A, 4.00%, 04/01/52		1,000		920,968

Security	Par (000)		Value
Florida (continued)
County of Miami-Dade Florida Water & Sewer System Revenue, RB, 4.00%, 10/01/48	$	1,000	$	933,816
Florida Development Finance Corp., RB
Series A, 4.00%, 06/15/42		500		406,451
Series A, 5.00%, 06/15/47		375		353,424
St Lucie County School Board, COP, Series A, (AGM), 5.00%, 07/01/48		1,500		1,581,844
				4,196,503
Georgia — 0.7%
Georgia Housing & Finance Authority, Refunding RB, Series A, 4.00%, 06/01/49		325		320,884
Illinois — 6.0%
Chicago Board of Education, GO
Series A, 5.00%, 12/01/47		500		488,203
Series A, AMT, 5.00%, 12/01/33		500		516,766
Chicago Transit Authority Sales Tax Receipts Fund, Refunding RB, Series A, 2nd Lien, 5.00%, 12/01/57		1,200		1,237,707
Illinois Housing Development Authority, RB, S/F Housing, Series G, (FHLMC, FNMA, GNMA), 6.25%, 10/01/52		340		364,976
Illinois Housing Development Authority, Refunding RB, Series H, (FHLMC, FNMA, GNMA), 5.75%, 10/01/53		215		227,903
				2,835,555
Kentucky — 3.2%
City of Henderson Kentucky, RB, Series A, AMT, 4.70%, 01/01/52(b)		500		468,725
Louisville/Jefferson County Metropolitan Government, RB, Series A, (AGM), 5.00%, 05/15/47		1,000		1,043,279
				1,512,004
Louisiana — 2.5%
Jefferson Parish Consolidated Sewerage District No. 1, RB, (BAM), 4.00%, 02/01/39		1,000		953,375
Louisiana Public Facilities Authority, RB, Series A, 6.38%, 06/01/52(b)		250		229,691
				1,183,066
Maine — 0.1%
Finance Authority of Maine, RB, AMT, 8.00%, 12/01/51(b)		100		62,424
Maryland — 1.5%
Maryland Economic Development Corp., RB, Class B, AMT, 5.25%, 06/30/47		715		726,914
Massachusetts — 5.4%
Massachusetts Bay Transportation Authority Assessment Revenue, Refunding RB, Series A, 5.00%, 07/01/52		1,500		1,595,720
University of Massachusetts Building Authority, RB, Series 1, 4.00%, 11/01/46		1,000		947,575
				2,543,295
Michigan — 5.0%
Ludington Area School District, GO, Series II, (BAM Q-SBLF), 4.00%, 05/01/51		1,000		912,739

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Schedule of Investments (unaudited) (continued) August 31, 2023 BlackRock Impact Municipal Fund (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Michigan (continued)
Michigan Finance Authority, RB, 4.00%, 02/15/47	$	500	$	447,923
Michigan State Housing Development Authority, RB, M/F Housing, Series A, 5.10%, 10/01/53		1,000		1,013,400
				2,374,062
Minnesota — 1.8%
Duluth Economic Development Authority, RB, Class B, 5.25%, 06/15/42		500		498,067
Minnesota Housing Finance Agency, RB, S/F Housing, Series N, (FHLMC, FNMA, GNMA), 6.00%, 01/01/53		340		361,832
				859,899
Mississippi — 0.2%
Mississippi Business Finance Corp., RB, AMT, 7.75%, 07/15/47(a)		100		77,865
New Hampshire — 1.5%
New Hampshire Business Finance Authority, RB, M/F Housing, Series 2022, Class A, 4.38%, 09/20/36		739		714,911
New Jersey — 0.2%
Camden County Improvement Authority, RB, 6.00%, 06/15/47		115		117,690
New York — 15.0%
Battery Park City Authority, RB, Sustainability Bonds, 4.00%, 11/01/44		1,500		1,450,330
Build NYC Resource Corp., RB 5.75%, 06/01/42(b)		250		250,678
5.50%, 06/15/63(b)		250		233,451
Series A, 5.00%, 07/01/32		245		227,433
Metropolitan Transportation Authority, Refunding RB, Series A-1, 5.00%, 11/15/49		1,000		1,013,205
Nassau County Local Economic Assistance Corp., RB, 5.00%, 07/01/43		1,000		991,554
New York City Housing Development Corp., RB, M/F Housing
Class F-1, 4.75%, 11/01/47		1,000		983,921
Series A, Sustainability Bonds, 4.60%, 11/01/43		225		221,317
New York Power Authority, RB, (AGM), 4.00%, 11/15/40		1,000		989,364
New York State Housing Finance Agency, RB, M/F Housing, (SONYMA), 3.80%, 11/01/62(a)		735		724,293
				7,085,546
North Carolina — 0.5%
North Carolina Housing Finance Agency, RB, S/F Housing, (FHLMC, FNMA, GNMA), 3.75%, 07/01/52		240		234,506
North Dakota — 1.4%
North Dakota Housing Finance Agency, RB, S/F Housing
5.75%, 01/01/54		400		423,808
Series A, 4.00%, 01/01/53		225		221,689
				645,497
Ohio — 0.3%
Southern Ohio Port Authority, RB, Series A, AMT, 7.00%, 12/01/42(b)		200		147,364
Oregon — 2.0%
Port of Portland Oregon Airport Revenue, Refunding ARB, 29th Series, AMT, 5.50%, 07/01/48		410		440,609
State of Oregon Housing & Community Services Department, RB, S/F Housing, Series A, AMT, 4.00%, 07/01/51		520		513,534
				954,143

Security	Par (000)		Value
Pennsylvania — 6.1%
City of Philadelphia Pennsylvania Water & Wastewater Revenue, RB, Series C, 5.50%, 06/01/47	$	1,000	$	1,084,681
Pennsylvania Housing Finance Agency, Refunding RB, Series 2022, 4.25%, 10/01/52		465		461,612
Pittsburgh Water & Sewer Authority, RB, Series A, 1st Lien, (AGM), 5.00%, 09/01/48		225		236,555
Southeastern Pennsylvania Transportation Authority, RB, 5.25%, 06/01/47		1,000		1,084,041
				2,866,889
Tennessee — 0.4%
Tennessee Housing Development Agency, Refunding RB, Series 1, 3.75%, 07/01/52		200		195,133
Texas — 6.5%
Arlington Higher Education Finance Corp., RB
(PSF), 5.00%, 08/15/47		500		524,356
Series A, 5.25%, 08/15/32		250		243,148
City of El Paso Texas Water & Sewer Revenue, Refunding RB, 5.00%, 03/01/46		1,000		1,045,786
New Hope Cultural Education Facilities Finance Corp., Refunding RB, Series A, 6.63%, 10/01/43		100		89,214
Tarrant County Cultural Education Facilities Finance Corp., RB, Class F, 5.00%, 11/15/52(a)		415		453,021
Texas State Technical College, RB, (AGM), 5.50%, 08/01/42		665		733,144
				3,088,669
Utah — 3.6%
University of Utah, RB, Series A, 4.00%, 08/01/43		1,500		1,450,305
Utah Infrastructure Agency, RB, 5.00%, 10/15/32		250		256,068
				1,706,373
Virginia — 2.1%
Henrico County Economic Development Authority, RB, Class A, 5.00%, 10/01/47		1,000		983,299
Total Long-Term Investments — 97.4% (Cost: $48,271,325)				46,106,364
	Shares
Short-Term Securities
Money Market Funds — 1.4%
BlackRock Liquidity Funds, MuniCash, Institutional Class, 4.03%(d)(e)		658,401		658,401
Total Short-Term Securities — 1.4% (Cost: $658,275)				658,401
Total Investments — 98.8% (Cost: $48,929,600)				46,764,765
Other Assets Less Liabilities — 1.2%			571,709
Net Assets — 100.0%			$ 47,336,474

^(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.

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Schedule of Investments (unaudited) (continued) August 31, 2023 BlackRock Impact Municipal Fund

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.

Affiliates

Investments in issuers considered to be affiliate(s) of the Fund during the period ended August 31, 2023 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 05/31/23		Purchases at Cost		Proceeds from Sales			Net Realized Gain (Loss)		Change in Unrealized Appreciation (Depreciation)			Value at 08/31/23		Shares Held at 08/31/23		Income		Capital Gain Distributions from Underlying Funds
BlackRock Liquidity Funds, MuniCash, Institutional Class	$	3,006,316	$	—	$	(2,347,961	)(a)	$	275	$	(229	)	$	658,401		658,401	$	17,184	$	—

^(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		28		12/19/23	$	3,108	$	(18,700	)
U.S. Long Bond		34		12/19/23		4,133		(38,530	)
5-Year U.S. Treasury Note		14		12/29/23		1,497		(10,560	)
							$	(67,790	)

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.

3

Schedule of Investments (unaudited) (continued) August 31, 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	$	—		$	46,036,278	$	70,086	$	46,106,364
Short-Term Securities
Money Market Funds		658,401			—		—		658,401
	$	658,401		$	46,036,278	$	70,086	$	46,764,765
Derivative Financial Instruments(a)
Liabilities
Interest Rate Contracts	$	(67,790	)	$	—	$	—	$	(67,790	)

^(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
ARB	Airport Revenue Bonds
BAM	Build America Mutual Assurance Co.
COP	Certificates of Participation
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
SONYMA	State of New York Mortgage Agency
ST	Special Tax

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