Blackrock California Municipal Series Trust NPORT-P BlackRock California Municipal Opportunities Fund (Aug 2020 report)

Schedule of Investments  (unaudited) August 31, 2020 BlackRock California Municipal Opportunities Fund (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Corporate Bonds
Education — 0.0%
University of Southern California, 3.03%, 10/01/39	$	650	$	717,518
Total Corporate Bonds — 0.0% (Cost: $591,769)				717,518
Municipal Bonds
California — 80.5%
Corporate — 0.8%
California Municipal Finance Authority, RB, AMT,
4.00%, 07/15/29.		8,645		8,536,765
California Pollution Control Financing Authority,
Refunding RB, Series A, AMT, 0.50%, 08/01/23(a)(b)		17,500		17,079,072
				25,615,837
County/City/Special District/School District — 29.3%
Butte-Glenn Community College District, GO, Series A, 5.25%, 08/01/46		12,360		15,206,508
Cerritos Community College District, GO, Series A, 4.00%, 08/01/44.		36,455		40,187,992
City & County of San Francisco California, Refunding COP
Series A, 4.00%, 04/01/41		5,705		6,440,203
Series A, 4.00%, 04/01/42		8,000		9,012,960
City of Los Angeles California, COP, (AMBAC), 6.20%, 11/01/31		4,000		4,019,040
Coast Community College District, GO, CAB, Series B, (AGM), 0.00%, 08/01/30(c)		26,425		23,322,969
County of Santa Clara California, GO, 4.00%, 08/01/42		14,995		15,875,057
Evergreen School District, GO
0.05%, 08/01/22.		1,410		1,406,405
0.05%, 08/01/23.		1,435		1,429,188
0.05%, 08/01/24.		1,460		1,448,787
Fremont Unified School District/Alameda County California, GO
Series A, 4.00%, 08/01/46		66,330		73,176,583
Series C, 4.00%, 08/01/38		1,510		1,725,764
Fremont Union High School District, GO
4.00%, 08/01/44.		36,730		40,877,552
Series A, 4.00%, 08/01/46		10,000		11,471,700
Glendale Community College District, GO, Series A, 5.25%, 08/01/41.		10,450		13,078,802
Grossmont-Cuyamaca Community College District, GO, 5.00%, 08/01/44		30,215		37,742,161
Hacienda La Puente Unified School District, GO, Series A, 5.25%, 08/01/42		5,000		6,269,250
Los Altos Elementary School District, Refunding GO, Series A-1, 4.00%, 08/01/44		5,000		5,778,200
Los Angeles Community College District, GO
Series F, 4.00%, 08/01/34		10,000		11,025,500
Series G, 4.00%, 08/01/39		5,645		6,291,522
Series K, 4.00%, 08/01/37		10,000		11,499,200
Series K, 4.00%, 08/01/38		29,760		34,015,978
Series K, 4.00%, 08/01/39		22,740		25,943,156
Los Angeles County Facilities Inc., RB, Series A, 5.00%, 12/01/43		4,000		4,885,000

Security	Par (000)		Value
County/City/Special District/School District (continued)
Los Angeles County Metropolitan Transportation Authority, RB, Series A, 5.00%, 06/01/24	$	9,940	$	11,693,018
Los Angeles County Metropolitan Transportation Authority, Refunding RB
Series A, 5.00%, 07/01/37		19,235		24,019,129
Series A, 5.00%, 07/01/44		25,885		32,850,136
Marin Healthcare District, GO
Series A, 4.00%, 08/01/40		11,550		12,951,246
Series A, 5.00%, 08/01/41		21,670		26,710,442
Menifee Union School District, GO, Series A, 5.25%, 08/01/42		7,275		9,064,868
Mount San Antonio Community College District, Refunding GO, Series A, 5.00%, 08/01/44		10,000		12,806,700
Mountain View-Whisman School District, GO,
Series B, 4.00%, 09/01/42		12,000		13,727,520
Municipal Improvement Corp. of Los Angeles,
Refunding RB
Series A, 5.00%, 11/01/22		1,480		1,631,463
Series A, 5.00%, 11/01/23		2,295		2,637,850
Series A, 5.00%, 11/01/24		5,640		6,730,325
Series B, 5.00%, 11/01/22		3,175		3,501,009
Series B, 5.00%, 11/01/23		2,000		2,298,760
Series B, 5.00%, 11/01/24		3,475		4,146,822
Orange County Local Transportation Authority, RB, 5.00%, 02/15/40		5,000		6,460,650
Palomar Community College District, GO, Series D, 5.25%, 08/01/45		3,000		3,774,120
Pomona Redevelopment Agency Successor Agency, Refunding TA, 3.98%, 02/01/27		4,155		4,752,946
Riverside County Public Financing Authority, RB, 5.25%, 11/01/45		11,210		13,391,802
San Diego Community College District, Refunding GO
5.00%, 08/01/22(d)		21,370		23,324,500
5.00%, 08/01/41		20,000		24,232,000
San Diego Unified School District, GO, Series D-2, 5.00%, 07/01/22		25,000		27,198,000
San Francisco Bay Area Rapid Transit District, GO
Series A, 5.00%, 08/01/47		8,980		10,928,660
Series C-1, 4.00%, 08/01/45		9,000		10,607,760
San Francisco Bay Area Rapid Transit District,
Refunding GO, Series D, 4.00%, 08/01/35		5,985		6,834,930
San Francisco City & County Redevelopment Agency Successor Agency, Refunding TA
Series D, 3.13%, 08/01/28		1,150		1,256,490
Series D, 3.25%, 08/01/29		1,000		1,092,470
Series D, 3.38%, 08/01/30		1,250		1,366,613
San Francisco City & County Redevelopment Financing Authority, TA, Series A, (BHAC), 5.75%, 08/01/37		9,500		13,248,605
San Francisco Unified School District, Refunding GO
4.00%, 06/15/21		15,000		15,451,200
4.00%, 06/15/22		18,140		19,373,701
4.00%, 06/15/23		16,690		18,454,133
San Joaquin County Transportation Authority, Refunding RB, 5.00%, 03/01/41		17,955		21,810,118
San Jose Evergreen Community College District, GO, Series C, 4.13%, 09/01/43		18,435		20,535,484
San Jose Financing Authority, RB, 5.75%, 05/01/42		2,010		2,075,707

SCHEDULE OF INVESTMENTS 1

Schedule of Investments  (unaudited) (continued) August 31, 2020 BlackRock California Municipal Opportunities Fund (Percentages shown are based on Net Assets)

Security	Par (000)		Value
County/City/Special District/School District (continued)
San Jose Unified School District, GO, CAB,
Series C, (NPFGC), 0.00%, 06/01/31(c)	$	25,000	$	21,147,250
San Leandro Unified School District, GO, Series A, 5.75%, 08/01/41		5,000		5,222,300
San Mateo County Community College District, GO, Series B, 5.00%, 09/01/45		32,650		40,991,422
Santa Clara County Financing Authority, RB,
Series A, 4.00%, 04/01/35		6,975		8,173,026
Santa Monica Community College District, GO,
Series B, 4.00%, 08/01/44		40,015		44,058,516
Vista Joint Powers Financing Authority, Refunding RB, 5.25%, 05/01/37		15,065		17,967,724
				950,628,892
Education — 5.2%
California Educational Facilities Authority, RB
Series A, 3.43%, 04/01/30		1,000		1,063,350
Series A, 3.56%, 04/01/31		2,000		2,129,820
California Infrastructure & Economic Development Bank, RB(a)
Series A, 4.13%, 01/01/35		1,010		992,931
Series A, 5.00%, 01/01/55		2,300		2,333,028
Series A-2, 5.00%, 01/01/24		920		922,300
California Infrastructure & Economic Development Bank, RB, CAB(c)
0.00%, 01/01/35		2,750		1,116,032
0.00%, 01/01/60		37,500		2,706,750
California Municipal Finance Authority, RB
6.00%, 07/01/44		500		520,085
Series A, 5.50%, 08/01/34(a)		300		316,971
California Municipal Finance Authority, Refunding RB
5.00%, 08/01/39		1,785		1,871,537
5.00%, 08/01/48		2,140		2,232,063
California Public Finance Authority, RB(a)
Series A, 5.00%, 07/01/36		385		397,297
Series A, 5.00%, 07/01/44		375		380,021
Series A, 5.00%, 07/01/54		520		525,008
Series B, 5.00%, 07/01/26		265		264,494
California School Finance Authority, RB(a)
5.00%, 06/01/40		1,420		1,497,177
5.00%, 06/01/50		2,240		2,337,350
5.00%, 06/01/59		3,565		3,705,318
Series A, 5.00%, 06/01/33		525		560,679
Series A, 5.00%, 06/01/43		525		547,250
Series A, 5.00%, 06/01/49		7,105		7,153,740
Series A, 6.00%, 07/01/51		1,500		1,600,230
Series A, 5.00%, 06/01/55		1,000		1,034,890
Series A, 5.00%, 06/01/58		3,355		3,358,892
Series A, 6.00%, 06/01/59		8,925		9,118,851
Series B, 6.00%, 06/01/31		735		697,919
California State University, RB(e)
Series C, 4.00%, 11/01/45		15,480		18,262,375
Series D, 1.69%, 11/01/29		5,000		5,001,550
California State University, Refunding RB, Series A, 5.00%, 11/01/41		31,145		37,354,690
California Statewide Communities Development Authority, RB, 5.00%, 06/01/51(a)		1,035		1,048,683
California Statewide Communities Development Authority, Refunding RB(a)
Series A, 5.00%, 06/01/36		2,900		2,971,253

Security	Par (000)		Value
Education (continued)
Series A, 5.00%, 06/01/46	$	4,100	$	4,137,720
San Francisco City & County Airport Comm-San Francisco International Airport, Refunding RB, AMT, 5.00%, 05/01/41		22,920		26,596,826
University of California, RB
6.30%, 05/15/50		3,790		5,035,394
Series AV, 5.25%, 05/15/42		12,220		15,175,896
Series BG, 1.32%, 05/15/27		3,160		3,207,811
				168,176,181
Health — 2.4%
California Health Facilities Financing Authority, RB
Series A, 5.00%, 11/15/36		2,755		3,375,867
Series A, 5.00%, 11/15/40		20,220		21,203,905
Series A, 5.25%, 11/01/41		7,000		7,346,220
Series A, 5.00%, 11/15/41		4,175		4,869,971
California Health Facilities Financing Authority, Refunding RB
5.00%, 11/15/38		15,050		18,292,221
Series A, 4.00%, 11/15/40		5,140		5,843,203
Series A-2, 4.00%, 11/01/38		5,005		5,692,487
California Municipal Finance Authority, Refunding RB(a)
Series A, 5.00%, 11/01/39		980		1,049,992
Series A, 5.00%, 11/01/49		1,105		1,155,023
California Statewide Communities Development Authority, RB, Series A, 5.00%, 04/01/42		10,000		10,619,200
				79,448,089
Housing — 0.2%
California Community Housing Agency, RB, M/F Housing, Series A, 5.00%, 04/01/49(a)		3,230		3,617,309
California Municipal Finance Authority, RB, 1.61%, 11/01/23		1,500		1,525,155
				5,142,464
Other — 4.9%
California Infrastructure & Economic Development Bank, RB
5.00%, 08/01/38		1,130		1,447,417
5.00%, 08/01/44		22,275		28,170,301
California Statewide Communities Development Authority, SAB
Series A, 5.00%, 09/02/39		1,375		1,559,745
Series A, 5.00%, 09/02/44		675		745,166
Series A, 5.00%, 09/02/48		675		737,208
City & County of San Francisco California Community Facilities District No. 2014-1, ST
Series B, 3.78%, 09/01/30		1,110		1,246,319
Series B, 3.92%, 09/01/31		3,410		3,843,786
Series B, 3.97%, 09/01/32		1,880		2,115,489
Series B, 4.02%, 09/01/33		2,070		2,325,749
City of Los Angeles California, RB, 4.00%, 06/24/21		64,000		65,974,400
City of San Jose California Hotel Tax Revenue, RB, 6.50%, 05/01/42		2,395		2,479,951
Hastings Campus Housing Finance Authority, RB(e)
Series A, 5.00%, 07/01/45		2,530		2,592,162
Series A, 5.00%, 07/01/61		15,170		15,223,247
Imperial Irrigation District, RB, (AMBAC), 6.94%, 01/01/26		15,570		18,863,055

2

Schedule of Investments  (unaudited) (continued) August 31, 2020 BlackRock California Municipal Opportunities Fund (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Other (continued)
San Francisco City & County Redevelopment Agency Successor Agency, TA, Series D, 0.00%, 08/01/31(a)(c)	$	3,000	$	1,781,190
San Francisco City & County Redevelopment Agency Successor Agency, TA, CAB, Series D, 0.00%, 08/01/23(a)(c)		1,000		887,130
San Jose Redevelopment Agency Successor Agency, Refunding TA, Series A-T, 3.25%, 08/01/29		8,730		9,741,283
				159,733,598
State — 5.0%
California State Public Works Board, RB
Series A, 5.00%, 09/01/34		500		576,340
Series A, 5.00%, 09/01/39		5,000		5,740,150
Series C, 5.00%, 11/01/36		2,145		2,794,013
Series C, 5.00%, 11/01/37		5,810		7,560,262
Series C, 5.00%, 11/01/38		5,000		6,496,250
Series C, 5.00%, 11/01/44		25,000		32,060,250
Series I, 5.25%, 11/01/32		1,115		1,279,396
Series I, 5.50%, 11/01/33		2,315		2,670,167
California State Public Works Board, Refunding RB, Series C, 5.00%, 11/01/33		10,000		12,293,700
County of Los Angeles California, RB, Series A, 4.00%, 06/30/21		81,000		83,549,880
State of California, Refunding GO
5.25%, 02/01/30		7,725		8,251,845
5.25%, 10/01/39		—		—
				163,272,253
Tobacco — 4.0%
California County Tobacco Securitization Agency, Refunding RB
5.25%, 06/01/46		11,500		11,396,155
Series A, 5.00%, 06/01/36		2,410		2,410,048
Series A, 5.13%, 06/01/38		955		957,034
Series A, 5.25%, 06/01/45		4,765		4,777,723
Series A, 5.00%, 06/01/47		2,595		2,584,516
Series A, 4.00%, 06/01/49		1,540		1,718,193
Series B-2, 0.00%, 06/01/55(c)		15,770		2,798,860
Golden State Tobacco Securitization Corp., Refunding RB
Series A-1, 5.00%, 06/01/47		13,125		13,448,925
Series A-2, 5.00%, 06/01/47		55,680		57,054,739
Inland Empire Tobacco Securitization Corp., Refunding RB, 3.68%, 06/01/38		5,470		5,742,242
Silicon Valley Tobacco Securitization Authority, RB, CAB, Series D, 0.00%, 06/01/56(c)		29,500		2,155,860
Tobacco Securitization Authority of Northern California, Refunding RB, Asset-Backed Bonds, 5.38%, 06/01/38		5,350		5,364,392
Tobacco Securitization Authority of Southern California, Refunding RB, 5.00%, 06/01/48		15,670		18,515,132
				128,923,819
Transportation — 10.1%
Bay Area Toll Authority, Refunding RB, 4.00%, 04/01/34		8,075		9,436,768
Burbank-Glendale-Pasadena Airport Authority Brick Campaign, RB, Series B, 5.56%, 07/01/32		1,000		1,198,110

Security	Par (000)		Value
Transportation (continued)
City of Long Beach California Harbor Revenue, RB, Series A, 5.00%, 05/15/44	$	10,000	$	12,467,300
City of Los Angeles Department of Airports, RB 5.00%, 05/15/41		18,710		21,703,039
Series A, AMT, 5.00%, 05/15/40		6,615		7,606,655
Series A, AMT, 5.00%, 05/15/42		33,725		39,476,791
Series D, AMT, 5.00%, 05/15/41		8,850		10,151,746
City of Los Angeles Department of Airports, Refunding RB
Series A, 5.00%, 05/15/36		11,260		14,408,972
Series A, 5.00%, 05/15/38		7,045		8,955,956
Series A, 5.00%, 05/15/39		7,000		8,873,830
Los Angeles County Metropolitan Transportation Authority, Refunding RB, Series A, 5.00%, 07/01/42		10,000		12,386,500
Norman Y Mineta San Jose International Airport SJC, Refunding RB
Series A, AMT, 5.00%, 03/01/41		20,000		23,361,600
Series A-1, AMT, 5.75%, 03/01/34		6,720		6,879,936
Series A-1, AMT, 6.25%, 03/01/34		2,920		2,996,708
Port of Oakland, Refunding RB, Series P, AMT, Senior Lien, 5.00%, 05/01/27		12,850		13,784,195
San Francisco City & County Airport Comm-San Francisco International Airport, RB, 5.25%, 05/01/42		40,370		48,259,105
San Francisco City & County Airport Comm-San Francisco International Airport, Refunding RB
Series C, 5.00%, 05/01/46		1,640		1,916,553
Series A, AMT, 5.00%, 05/01/39		5,125		5,778,489
Series A, AMT, 5.00%, 05/01/40		14,000		15,767,220
Series A, AMT, 5.00%, 05/01/42		29,480		34,660,226
Series A, AMT, 5.00%, 05/01/44		15,125		17,394,749
Series E, AMT, 5.00%, 05/01/38		9,010		11,118,340
San Francisco Municipal Transportation Agency, RB, 5.00%, 03/01/24		1,200		1,327,080
				329,909,868
Utilities — 18.6%
Chino Basin Regional Financing Authority, RB, Series B, 4.00%, 11/01/25		50,000		59,154,000
City of Los Angeles California Wastewater System Revenue, RB, Series A, 5.25%, 06/01/47		20,000		24,957,800
City of Los Angeles California Wastewater System Revenue, Refunding RB
Series A, 5.00%, 06/01/38		2,000		2,541,000
Series A, 5.00%, 06/01/43		10,000		12,569,000
Series C, 5.00%, 06/01/35		4,520		5,444,024
City of Riverside California Electric Revenue, RB, 7.61%, 10/01/40.		2,500		4,122,175
City of Sacramento California Water Revenue, RB, 5.00%, 09/01/42.		6,465		8,012,721
City of San Francisco California Public Utilities Commission Water Revenue, Refunding RB, Series A, 4.00%, 11/01/30		19,910		23,771,146
East Bay Municipal Utility District Water System Revenue, RB, Series A, 4.00%, 06/01/45		5,885		6,762,630
East Bay Municipal Utility District Water System Revenue, Refunding RB, Series A, 5.00%, 06/01/37		7,160		8,565,150

SCHEDULE OF INVESTMENTS 3

Schedule of Investments  (unaudited) (continued) August 31, 2020 BlackRock California Municipal Opportunities Fund (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Utilities (continued)
Eastern Municipal Water District Financing Authority, RB, Series D, 5.25%, 07/01/42	$	18,500	$	23,367,165
Los Angeles Department of Water, Refunding RB
Series A, 5.25%, 07/01/39		8,000		8,126,000
Series A, 5.00%, 07/01/41		52,560		63,598,653
Series A, 5.25%, 07/01/44		10,650		13,184,061
Metropolitan Water District of Southern California, RB, Series A, 5.00%, 07/01/40		16,105		19,316,659
Metropolitan Water District of Southern California, Refunding RB
5.00%, 01/01/38.		7,000		8,965,180
Series A, 5.00%, 10/01/35		5,000		5,365,350
Northern California Power Agency, RB, Series A, 7.31%, 06/01/40		2,150		3,197,888
Sacramento Municipal Utility District, RB
Series G, 5.00%, 08/15/38		22,390		29,166,557
Series G, 5.00%, 08/15/41		20,000		25,876,200
Sacramento Municipal Utility District, Refunding RB,
Series H, 4.00%, 08/15/40		3,000		3,685,650
San Diego County Water Authority, Refunding RB
5.00%, 11/01/22(d)		6,000		6,620,700
Series B, 5.00%, 05/01/38		20,405		24,926,952
San Diego Public Facilities Financing Authority, Refunding RB
Series A, 5.00%, 05/15/36		5,000		6,135,350
Series A, 5.00%, 05/15/38		13,595		16,640,960
Series A, 5.00%, 08/01/43		33,000		41,081,370
Series A, 5.25%, 08/01/47		15,180		19,054,088
Series B, 5.00%, 08/01/38		16,460		20,238,064
San Francisco City & County Public Utilities Commission Wastewater Revenue, Refunding RB
Series A, 5.00%, 10/01/31		5,000		6,146,950
Series A, 5.00%, 10/01/32		5,000		6,133,650
Series B, 4.00%, 10/01/42		17,010		18,169,912
Southern California Public Power Authority, Refunding RB, 5.00%, 07/01/30		41,400		47,557,836
State of California Department of Water Resources, Refunding RB
Series AW, 4.00%, 12/01/34		24,000		28,297,680
Series BC, 1.32%, 12/01/28.		4,000		4,021,560
				604,774,081
Total Municipal Bonds in California				2,615,625,082
Connecticut — 0.2%
Corporate — 0.2%
Mashantucket Western Pequot Tribe, 7.35%, 07/01/26		36,909		6,090,002
Illinois — 1.1%
County/City/Special District/School District — 1.1%
Chicago Board of Education, GO
6.32%, 11/01/29		3,650		3,884,221
6.04%, 12/01/29.		7,590		7,974,206
6.14%, 12/01/39.		13,850		14,552,333
6.52%, 12/01/40.		8,075		8,655,673
Total Municipal Bonds in Illinois				35,066,433

Security	Par (000)		Value
Ohio — 0.9%
Tobacco — 0.9%
Buckeye Tobacco Settlement Financing Authority, Refunding RB, Series B-2, Class 2, 5.00%, 06/01/55	$	28,375	$	31,110,634
Puerto Rico — 7.8%
State — 4.8%
Commonwealth of Puerto Rico, GO(f)(g)
Series A, 5.25%, 07/01/22		940		665,898
Series A, 5.25%, 07/01/26		330		233,773
Series A, 5.13%, 07/01/31		3,340		2,366,063
Series A, 5.38%, 07/01/33		1,025		726,112
Series A, 6.00%, 07/01/38		1,630		1,164,981
Commonwealth of Puerto Rico, Refunding GO(f)(g) 5.00%, 07/01/18		470		320,450
Series A, 5.50%, 07/01/18		1,025		698,853
Series A, 5.50%, 07/01/32		1,170		828,830
Series A, 6.00%, 07/01/34		955		682,550
Series A, 8.00%, 07/01/35		27,405		16,682,794
Series A, 5.50%, 07/01/39		8,805		5,761,164
Series A, 5.00%, 07/01/41		10,546		6,482,459
Series A, 5.75%, 07/01/41		1,110		737,456
Series B, 6.00%, 07/01/39		3,970		2,837,407
Series C, 6.00%, 07/01/39		470		335,915
Puerto Rico Public Buildings Authority, Refunding RB(f)(g)
Series F, (GTD), 5.25%, 07/01/24		500		389,404
Series M-2, (GTD), 10.00%, 07/01/34(b)		1,045		877,800
Puerto Rico Sales Tax Financing Corp. Sales Tax Revenue, RB
Series A-1, Restructured, 0.00%, 07/01/29(c)		1,117		886,663
Series A-1, Restructured, 0.00%, 07/01/31(c)		1,330		977,364
Series A-1, Restructured, 0.00%, 07/01/33(c)		1,909		1,281,779
Series A-1, Restructured, 0.00%, 07/01/51(c)		6,760		1,396,143
Series A-1, Restructured, 4.75%, 07/01/53		31,268		32,728,841
Series A-1, Restructured, 5.00%, 07/01/58		11,287		12,016,817
Series A-2, Restructured, 4.33%, 07/01/40		12,198		12,699,264
Series A-2, Restructured, 4.54%, 07/01/53		114		117,953
Series A-2, Restructured, 4.78%, 07/01/58		20,042		21,102,021
Series B-1, Restructured, 0.00%, 07/01/46(c)		5,761		1,645,572
Puerto Rico Sales Tax Financing Corp. Sales Tax Revenue, RB, CAB, Series A-1, Restructured, 0.00%, 07/01/46(c)		106,226		30,313,714
				156,958,040
Tobacco — 0.1%
Children’s Trust Fund, RB, Asset-Backed Bonds, 0.00%, 05/15/57(c)		97,000		3,880,000
Utilities — 2.9%
City of New York Water & Sewer System, RB, Series 3, 5.40%, 01/01/21(b)(f)(g)		593		408,896
Puerto Rico Commonwealth Aqueduct & Sewer Authority, Refunding RB
Series B, Senior Lien, 5.00%, 07/01/23		4,000		3,967,400
Series B, Senior Lien, 5.35%, 07/01/27		6,705		6,404,281
Series B, Senior Lien, 6.15%, 07/01/38		3,620		3,489,644
Puerto Rico Electric Power Authority, RB
Series A, 5.00%, 07/01/29(f)(g)		4,130		2,845,628
Series A, 7.00%, 07/01/33(f)(g)		2,230		1,565,879
Series A, 6.75%, 07/01/36(f)(g)		7,630		5,357,694
Series A, 5.00%, 07/01/42(f)(g)		8,830		6,083,994

4

Schedule of Investments  (unaudited) (continued) August 31, 2020 BlackRock California Municipal Opportunities Fund (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Utilities (continued)
Series A, 7.00%, 07/01/43(f)(g)	$	955	$	670,590
Series A-3, 10.00%, 07/01/19(f)(g)		2,137		1,818,808
Series B-3, 10.00%, 07/01/19(f)(g)		2,137		1,818,808
Series C-1, 5.40%, 01/01/18(f)(g)		5,870		4,044,476
Series C-2, 5.40%, 07/01/18(f)(g)		5,871		4,045,131
Series C-4, 5.40%, 07/01/20(f)(g)		593		408,897
Series CCC, 5.25%, 07/01/26(f)(g)		1,680		1,157,544
Series CCC, 5.25%, 07/01/28(f)(g)		955		658,008
Series D-4, 7.50%, 07/01/20		1,638		1,150,184
Series TT, 5.00%, 07/01/25(f)(g)		480		330,727
Series TT, 5.00%, 07/01/26(f)(g)		1,285		885,383
Series TT, 5.00%, 07/01/32(f)(g)		1,075		740,690
Series WW, 5.50%, 07/01/17(f)(g)		1,315		906,053
Series WW, 5.50%, 07/01/18(f)(g)		1,155		795,811
Series WW, 5.50%, 07/01/19(f)(g)		935		644,228
Series WW, 5.38%, 07/01/22(f)(g)		1,250		861,268
Series WW, 5.38%, 07/01/24(f)(g)		875		602,887
Series WW, 5.25%, 07/01/33(f)(g)		885		609,777
Series WW, 5.50%, 07/01/38(f)(g)		1,170		806,146
Series XX, 5.25%, 07/01/27(f)(g)		645		444,414
Series XX, 5.25%, 07/01/35(f)(g)		400		275,606
Series XX, 5.75%, 07/01/36(f)(g)		555		382,403
Series XX, 5.25%, 07/01/40(f)(g)		11,490		7,916,771
Puerto Rico Electric Power Authority, Refunding RB(f)(g)
Series AAA, 5.25%, 07/01/22		2,150		1,481,380
Series AAA, 5.25%, 07/01/24		480		330,727
Series AAA, 5.25%, 07/01/26		1,840		1,267,786
Series AAA, 5.25%, 07/01/27		6,540		4,506,152
Series AAA, 5.25%, 07/01/28		4,690		3,231,476
Series AAA, 5.25%, 07/01/29		530		365,177
Series BBB, 5.40%, 07/01/28		2,805		1,932,684
Series UU, 1.16%, 07/01/17(b)		395		256,750
Series UU, 1.00%, 07/01/18(b)		355		230,750
Series UU, 1.00%, 07/01/20(b)		3,175		1,906,587
Series UU, 0.90%, 07/01/31(h)		3,765		2,260,882
Series YY, 6.13%, 07/01/40		4,060		2,797,397
Series ZZ, 5.00%, 07/01/17		925		637,338
Series ZZ, 5.25%, 07/01/19		2,945		2,029,146
Series ZZ, 5.25%, 07/01/21		3,590		2,473,560
Series ZZ, 5.25%, 07/01/24		1,990		1,371,138
Series ZZ, 5.25%, 07/01/26		4,335		2,986,876
Series ZZ, 5.00%, 07/01/28		990		682,124
				92,845,956
Total Municipal Bonds in Puerto Rico				253,683,996
Total Municipal Bonds — 90.5% (Cost: $2,810,585,900)				2,941,576,147
Municipal Bonds Transferred to Tender Option Bond Trusts(i)
California — 10.7%
County/City/Special District/School District — 2.3%
Irvine Ranch Water District, COP, 5.00%, 03/01/46		19,330		23,620,873
Ohlone Community College District, GO, Series B, 4.00%, 08/01/44		47,250		52,150,298
				75,771,171
Education — 3.7%
California State University, Refunding RB, Series A, 5.00%, 11/01/43		35,250		43,719,165

Security	Par (000)		Value
Education (continued)
University of California, RB, Series M, 5.00%, 05/15/42	$	20,000	$	24,465,400
University of California, Refunding RB, Series AZ, 5.00%, 05/15/43.		41,740		51,503,404
				119,687,969
State — 0.7%
State of California, Refunding GO, 5.25%, 10/01/39		18,150		22,228,305
Utilities — 4.0%
East Bay Municipal Utility District Water System Revenue, RB, Series A, 5.00%, 06/01/42		27,045		33,484,132
Eastern Municipal Water District Financing Authority, RB, Series D, 5.00%, 07/01/47		36,105		44,301,198
San Francisco City & County Public Utilities Commission Wastewater Revenue, RB, Series B, 5.00%, 10/01/43.		41,405		52,093,268
				129,878,598
Total Municipal Bonds in California				347,566,043
Total Municipal Bonds Transferred to Tender Option Bond Trusts — 10.7% (Cost: $316,858,669)				347,566,043
Total Long-Term Investments — 101.2% (Cost: $3,128,036,338)				3,289,859,708
	Shares
Short-Term Securities
Money Market Funds — 4.0%
BlackRock Liquidity Funds California Money Fund, Institutional Class, 0.01%(j)(k)		129,315,748		129,328,679
Total Short-Term Securities — 4.0% (Cost: $129,314,891)				129,328,679
Total Investments — 105.2% (Cost: $3,257,351,229)				3,419,188,387
Liabilities in Excess of Other Assets — (0.8)%				(26,359,212	)
Liability for TOB Trust Certificates, Including Interest Expense and Fees Payable — (4.4)%				(143,187,952	)
Net Assets — 100.0%			$	3,249,641,223

^(a)  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.

^(b)  Variable or floating rate security, which interest rate adjusts periodically based on changes in current interest rates and prepayments on the underlying pool of assets. Rate shown is the rate in effect as of period end.

^(c)  Zero-coupon bond.

^(d)  U.S. Government securities held in escrow, are used to pay interest on this security as well as to retire the bond in full at the date indicated, typically at a premium to par.

^(e)  When-issued security.

^(f)  Issuer filed for bankruptcy and/or is in default.

^(g)  Non-income producing security.

^(h)  Variable rate security. Rate shown is the rate in effect as of period end.

⁽ⁱ⁾  Represent bonds transferred to a TOB Trust in exchange of cash and residual certificates received by the Fund. These bonds serve as collateral in a secured borrowing.

^(j)  Affiliate of the Fund.

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

SCHEDULE OF INVESTMENTS 5

Schedule of Investments  (unaudited) (continued) August 31, 2020 BlackRock California Municipal Opportunities Fund

Affiliates

Investments in issuers considered to be an affiliate of the Fund during the period ended August 31, 2020, for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 05/31/20		Purchases at Cost		Proceeds from Sales			Net Realized Gain (Loss)		Change in Unrealized Appreciation (Depreciation)			Value at 08/31/20		Shares Held at 08/31/20		Income		Capital Gain Distributions from Underlying Funds
BlackRock Liquidity Funds California Money Fund, Institutional Class	$	322,516,448	$	—	$	(193,159,708	)(a)	$	336	$	(28,397	)	$	129,328,679		129,315,748	$	5,254	$	—

^(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 US Treasury Notes.		4,284		12/21/20	$	596,547	$	(1,022,687	)
Long U.S. Treasury Bond		1,324		12/21/20		232,652		738,481
							$	(284,206	)

FairValue 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)

• Level 3 – Unobservable inputs based on the best information available in the circumstances, to the extent observable inputs are not available (including the BlackRock Global Valuation Methodologies Committee’s (the “Global 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 Global 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.

The following tables summarize the Fund’s investments and derivative financial instruments categorized in the disclosure hierarchy. The breakdown of the Fund’s investments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Long-Term Investments
Corporate Bonds	$	—	$	717,518	$	—	$	717,518
Municipal Bonds		—		2,941,576,147		—		2,941,576,147
Municipal Bonds Transferred to Tender Option Bond Trusts		—		347,566,043		—		347,566,043

6

Schedule of Investments  (unaudited) (continued) August 31, 2020 BlackRock California Municipal Opportunities Fund

FairValue Hierarchy as of Period End (continued)

	Level 1			Level 2		Level 3		Total
Short-Term Securities
Money Market Funds	$	129,328,679		$	—	$	—	$	129,328,679
	$	129,328,679		$	3,289,859,708	$	—	$	3,419,188,387
Derivative Financial Instruments(a)
Assets
Interest Rate Contracts	$	738,481		$	—	$	—	$	738,481
Liabilities
Interest Rate Contracts		(1,022,687	)		—		—		(1,022,687	)
	$	(284,206	)	$	—	$	—	$	(284,206	)

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

The Fund may hold assets and/or liabilities in which the fair value approximates the carrying amount for financial statement purposes. As of period end, TOB Trust Certificates of $143,144,977 are categorized as Level 2 within the disclosure hierarchy.

Portfolio Abbreviation
AGM	Assured Guaranty Municipal Corp.
AMBAC	AMBAC Assurance Corp.
AMT	Alternative Minimum Tax
BHAC	Berkshire Hathaway Assurance Corp.
CAB	Capital Appreciation Bonds
COP	Certificates of Participation
GO	General Obligation Bonds
GTD	GTD Guaranteed
M/F	Multi-Family
NPFGC	National Public Finance Guarantee Corp.
RB	Revenue Bond
SAB	Special Assessment Bonds
ST	Special Tax
TA	Tax Allocation

SCHEDULE OF INVESTMENTS 7