Quarterly Report

June 30, 2020

MFS^® West Virginia
Municipal Bond Fund

Portfolio of Investments

6/30/20 (unaudited)

The Portfolio of Investments is a complete list of all securities owned by your fund. It is categorized by broad-based asset classes.

Issuer		Shares/Par	Value ($)
Municipal Bonds – 96.6%
Airport Revenue – 0.5%
Dallas and Fort Worth, TX, International Airport Rev., “B”, 5%, 11/01/2044	$	155,000	$166,280
Dallas and Fort Worth, TX, International Airport Rev., “C”, 5%, 11/01/2045		110,000	114,732
Wayne County, MI, Airport Authority Rev. (Detroit Metropolitan Wayne County Airport), “B”, 5%, 12/01/2044		60,000	66,849
Wayne County, MI, Airport Authority Rev. (Detroit Metropolitan Wayne County Airport), “B”, BAM, 5%, 12/01/2039		70,000	78,491
Wayne County, MI, Airport Authority Rev. (Detroit Metropolitan Wayne County Airport), “C”, 5%, 12/01/2039		55,000	61,058
Wayne County, MI, Airport Authority Rev. (Detroit Metropolitan Wayne County Airport), “C”, 5%, 12/01/2044		85,000	93,763
			$581,173
General Obligations - General Purpose – 8.3%
Bridgeview, IL, Stadium and Redevelopment Projects, AAC, 5.14%, 12/01/2036	$	260,000	$249,036
Commonwealth of Puerto Rico, General Obligation, “A”, 8%, 7/01/2035 (a)(d)		1,100,000	660,000
Commonwealth of Puerto Rico, Public Improvement, “A-4”, AGM, 5%, 7/01/2031		95,000	95,403
State of Illinois, 5.5%, 5/01/2039		165,000	185,660
State of Illinois, “A”, 4%, 12/01/2033		40,000	39,528
State of West Virginia, General Obligation Road Bonds, “A”, 5%, 6/01/2027		720,000	926,726
State of West Virginia, General Obligation Road Bonds, “A”, 5%, 6/01/2044		3,000,000	3,795,390
State of West Virginia, General Obligation Road Bonds, “B”, 5%, 12/01/2021		1,905,000	2,032,063
State of West Virginia, General Obligation Road Bonds, “B”, 4%, 12/01/2042		1,000,000	1,126,760
			$9,110,566
General Obligations - Schools – 4.3%
Hancock County, WV, Board of Education, Public School General Obligation, 4.5%, 5/01/2032	$	1,405,000	$1,454,035
Monongalia County, WV, Board of Education, 5%, 5/01/2031		2,000,000	2,170,300
Putnam County, WV, Board of Education, 4%, 5/01/2025		1,000,000	1,011,880
			$4,636,215
Healthcare Revenue - Hospitals – 17.8%
Allegheny County, PA, Hospital Development Authority Rev. (Allegheny Health Network Obligated Group), “A”, 4%, 4/01/2044	$	190,000	$205,424
Doylestown, PA, Hospital Rev., “A”, 4%, 7/01/2045		15,000	15,718
Escambia County, FL, Health Facilities Authority Rev. (Baptist Hospital, Inc.), “A”, 6%, 8/15/2036		725,000	728,335
Monongalia County, WV, Building Commission Hospital Rev. (Monongalia General Hospital), 6.5%, 7/01/2041		1,100,000	1,146,376
New Hampshire Health & Education Facilities Authority Rev. (Dartmouth-Hitchcock Obligated Group), “A”, 5%, 8/01/2059		55,000	78,867
Spartanburg County, SC, Regional Health Services District Hospital Rev., “A”, 4%, 4/15/2043		780,000	843,180
Virginia Small Business Financing Authority Health Facilities Rev. (Bon Secours Mercy Health, Inc.), “A”, 4%, 12/01/2049		490,000	546,320
West Virginia Hospital Finance Authority Hospital Improvement Rev. (Cabell Huntington Hospital Obligated Group), 4%, 1/01/2038		230,000	250,346
West Virginia Hospital Finance Authority Hospital Improvement Rev. (Charleston Area Medical Center, Inc.), “A”, 5%, 9/01/2028		1,000,000	1,118,040
West Virginia Hospital Finance Authority Hospital Improvement Rev. (Charleston Area Medical Center, Inc.), “A”, 5%, 9/01/2039		1,500,000	1,721,430
West Virginia Hospital Finance Authority Hospital Improvement Rev. (Thomas Health System), 6.5%, 10/01/2038 (a)(d)		500,000	178,000
West Virginia Hospital Finance Authority Hospital Improvement Rev. (West Virginia University Health System Obligated Group), “A”, 4%, 6/01/2051		220,000	237,301
West Virginia Hospital Finance Authority Hospital Rev. (Cabell Huntington Hospital Obligated Group), “A”, 4.125%, 1/01/2047		1,000,000	1,073,260
West Virginia Hospital Finance Authority Hospital Rev. (Charleston Area Medical Center), “A”, ETM, 6.5%, 9/01/2023		1,250,000	1,360,362
West Virginia Hospital Finance Authority Hospital Rev. (Valley Health System Obligation Group), 5%, 1/01/2044		1,000,000	1,093,530
West Virginia Hospital Finance Authority Hospital Rev. (Valley Health System Obligation Group), 5%, 1/01/2044		1,000,000	1,130,050
West Virginia Hospital Finance Authority Hospital Rev. (West Virginia United Health System Obligated Group), “A”, 5%, 6/01/2027		200,000	237,312
West Virginia Hospital Finance Authority Hospital Rev. (West Virginia United Health System Obligated Group), “A”, 4%, 6/01/2035		1,500,000	1,637,850
West Virginia Hospital Finance Authority Hospital Rev. (West Virginia United Health System Obligated Group), “A”, 5.5%, 6/01/2044		1,460,000	1,595,605
West Virginia Hospital Finance Authority Hospital Rev. (West Virginia United Health System Obligated Group), “A”, AGM, 4%, 6/01/2051		2,000,000	2,186,900
West Virginia Hospital Finance Authority Hospital Rev. (West Virginia University Health System Obligated Group), “A”, 5%, 6/01/2042		1,000,000	1,150,340

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Healthcare Revenue - Hospitals – continued
West Virginia Hospital Finance Authority Hospital Rev. (West Virginia University Health System Obligated Group), “C”, VRDN, 0.1%, 6/01/2034	$	945,000	$945,000
			$19,479,546
Industrial Revenue - Airlines – 0.2%
New York Transportation Development Corp., Special Facilities Rev. (American Airlines, Inc. John F. Kennedy International Airport Project), 5%, 8/01/2020	$	200,000	$200,734
Industrial Revenue - Other – 1.0%
New York Liberty Development Corp. Rev. (Goldman Sachs Headquarters), 5.25%, 10/01/2035	$	420,000	$566,529
Port Beaumont, TX, Navigation District Facility Rev. (Jefferson Gulf Coast Energy Project), “A”, 4%, 1/01/2050 (n)		200,000	190,668
Tuscaloosa County, AL, Industrial Development Authority, Gulf Opportunity Zone (Hunt Refining Project), “A”, 5.25%, 5/01/2044		325,000	354,702
			$1,111,899
Miscellaneous Revenue - Other – 7.7%
Indiana Finance Authority Rev. (Ohio River Bridges East End Crossing Project), “A”, 5%, 7/01/2040	$	140,000	$149,080
New York Liberty Development Corp., Liberty Rev. (3 World Trade Center Project), “1”, 5%, 11/15/2044		580,000	601,129
New York Liberty Development Corp., Liberty Rev. (7 World Trade Center Project), 5%, 9/15/2040		545,000	577,324
West Virginia Economic Development Authority, Excess Lottery Rev., 5%, 6/15/2022		250,000	271,220
West Virginia Economic Development Authority, Excess Lottery Rev., “A”, 5%, 7/01/2038		1,000,000	1,240,570
West Virginia School Building Authority, “A”, 5%, 7/01/2028		590,000	710,089
West Virginia School Building Authority, “A”, 3%, 7/01/2033		2,000,000	2,183,220
West Virginia School Building Authority, Excess Lottery Rev., “B”, 5%, 7/01/2030		1,000,000	1,003,580
West Virginia School Building Authority, Lottery Capital Improvement Rev., “A”, 5%, 7/01/2028		1,500,000	1,697,970
			$8,434,182
Sales & Excise Tax Revenue – 5.1%
Guam Government Business Privilege Tax Rev., “A”, 5.25%, 1/01/2036	$	335,000	$344,363
Guam Government Business Privilege Tax Rev., “A”, 5.125%, 1/01/2042		790,000	808,605
Massachusetts Bay Transportation Authority, Sales Tax Rev., “A”, 5%, 7/01/2031		500,000	697,305
Metropolitan Pier & Exposition Authority Rev. (McCormick Place Expansion Project), “A”, AGM, 4%, 6/15/2050		835,000	864,576
Ohio County, WV, Commission Special District Excise Tax Improvement Refunding Rev. (Fort Henry Economic Opportunity Development District - The Highlands Project), “B”, 2.75%, 3/01/2041		455,000	453,644
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-1”, 4.55%, 7/01/2040		25,000	25,488
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-1”, 5%, 7/01/2058		988,000	1,033,003
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.329%, 7/01/2040		238,000	239,102
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.329%, 7/01/2040		83,000	83,384
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.536%, 7/01/2053		1,000	1,013
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.784%, 7/01/2058		39,000	40,211
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2024		3,000	2,703
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2027		45,000	37,037
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2029		7,000	5,344
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2031		412,000	290,069
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2033		396,000	255,986
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2046		1,503,000	423,921
			$5,605,754
Single Family Housing - State – 3.3%
Maryland Community Development Administration, Department of Housing & Community Development Housing Rev., “A”, 4.25%, 9/01/2049	$	510,000	$565,636
Tennessee Housing Development Agency Residential Finance Program, “1”, 4.25%, 1/01/2050		500,000	554,080
West Virginia Housing Development Fund, “A”, 3.8%, 11/01/2024		30,000	30,262
West Virginia Housing Development Fund, “A”, 3.875%, 11/01/2044		1,500,000	1,639,170
West Virginia Housing Development Fund, “A”, FHA, 3.9%, 11/01/2048		800,000	862,944
			$3,652,092

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
State & Local Agencies – 8.7%
California Municipal Finance Authority, Lease Rev. (Orange County Civic Center Infrastructure Improvement Program - Phase II), “A”, 5%, 6/01/2043	$	1,000,000	$1,201,030
Maryland Stadium Authority Rev., Baltimore City Public Schools Construction and Revitalization Program, “A”, 5%, 5/01/2047		400,000	473,244
New Jersey Economic Development Authority Rev., School Facilities Construction, “AAA”, 5%, 6/15/2026		105,000	118,567
North Carolina Turnpike Authority, Triangle Expressway System Appropriation Rev., Capital Appreciation, 0%, 1/01/2044		1,640,000	827,216
West Virginia Economic Development Authority, Auto Lease Rev., 5.2%, 5/01/2033		1,000,000	1,001,900
West Virginia Economic Development Authority, Lease Rev. (Correctional Juvenile Public Safety Facilities), 5%, 6/01/2022		1,000,000	1,041,260
West Virginia Economic Development Authority, Lease Rev. (Correctional Juvenile Public Safety Facilities), “A”, 5%, 6/01/2029		2,000,000	2,164,320
West Virginia Economic Development Authority, Lease Rev. (State Office Building), “B”, NATL, 5.25%, 1/01/2025		490,000	491,965
West Virginia Economic Development Authority, Lease Rev. (State Office Building), “B”, NATL, 5.25%, 1/01/2030		1,355,000	1,360,433
West Virginia Hospital Finance Authority Hospital Rev. (Veterans Nursing Home), 5.5%, 3/01/2034		795,000	796,781
			$9,476,716
Tax - Other – 2.9%
Birmingham-Jefferson, AL, Civic Center Authority, “B”, 5%, 7/01/2043	$	535,000	$525,771
Puerto Rico Convention Center District Authority, Hotel Occupancy Tax Rev., “A”, AAC, 5%, 7/01/2031		945,000	945,264
Puerto Rico Infrastructure Financing Authority Special Tax Rev., “C”, AAC, 5.5%, 7/01/2026		95,000	103,652
Puerto Rico Infrastructure Financing Authority Special Tax Rev., “C”, AAC, 5.5%, 7/01/2027		430,000	469,470
Virgin Islands Public Finance Authority Rev. (Gross Receipts), AGM, 5%, 10/01/2032		1,000,000	1,081,310
			$3,125,467
Tax Assessment – 1.3%
Morgantown, WV, Tax Increment Rev., Parking Garage Project, “A”, 5%, 6/01/2033	$	455,000	$434,534
Ohio County, WV, Commission Tax Increment Rev. (Fort Henry Centre), 4%, 6/01/2034		1,000,000	971,860
			$1,406,394
Tobacco – 1.4%
Buckeye, OH, Tobacco Settlement Financing Authority Senior Asset-Backed Refunding, 2020A-2, “1”, 5%, 6/01/2036	$	75,000	$95,472
Buckeye, OH, Tobacco Settlement Financing Authority Senior Asset-Backed Refunding, 2020A-2, “1”, 4%, 6/01/2048		125,000	135,091
Buckeye, OH, Tobacco Settlement Financing Authority Senior Asset-Backed Refunding, 2020B-2, “2”, 5%, 6/01/2055		415,000	436,991
Buckeye, OH, Tobacco Settlement Financing Authority Senior Asset-Backed Refunding, 2020B-3, Capital Appreciation, “2”, 0%, 6/01/2057		1,360,000	188,795
Illinois Railsplitter Tobacco Settlement Authority Rev., 6%, 6/01/2028 (Prerefunded 6/01/2021)		620,000	652,110
			$1,508,459
Toll Roads – 1.3%
Texas Private Activity Surface Transportation Corp., Senior Lien Rev. (NTE Mobility Partners Segments 3 LLC Segments 3A & 3B Facility), 7%, 12/31/2038	$	155,000	$177,613
Texas Private Activity Surface Transportation Corp., Senior Lien Rev. (NTE Mobility Partners Segments 3 LLC Segments 3A & 3B Facility), 6.75%, 6/30/2043		120,000	136,397
West Virginia Parkways Authority, Turnpike Toll Rev., 4%, 6/01/2047		1,000,000	1,128,570
			$1,442,580
Transportation - Special Tax – 4.6%
Commonwealth of Puerto Rico Highway & Transportation Authority Rev., “AA-1”, AGM, 4.95%, 7/01/2026	$	575,000	$578,536
Commonwealth of Puerto Rico Highway & Transportation Authority Rev., “L”, AAC, 5.25%, 7/01/2038		755,000	783,260
Commonwealth of Puerto Rico Highway & Transportation Authority Rev., “L”, ASSD GTY, 5.25%, 7/01/2041		160,000	173,352
Commonwealth of Puerto Rico Highway & Transportation Authority Rev., “L”, NATL, 5.25%, 7/01/2035		340,000	346,684
Commonwealth of Puerto Rico Highway & Transportation Authority Rev., “N”, AAC, 5.5%, 7/01/2029		760,000	828,613
Commonwealth of Puerto Rico Highway & Transportation Authority Rev., “N”, NATL, 5.25%, 7/01/2032		115,000	117,324
Metropolitan Transportation Authority Refunding Rev., NY (Climate Bond Certified), “C-1”, 4.75%, 11/15/2045		140,000	155,233
Metropolitan Transportation Authority Refunding Rev., NY (Climate Bond Certified), “C-1”, 5%, 11/15/2050		170,000	192,789
Metropolitan Transportation Authority Rev., NY, Anticipation Note, “B-2”, 5%, 5/15/2021		370,000	377,733
New Jersey Transportation Trust Fund Authority, Federal Highway Reimbursement Rev., “A-1”, 5%, 6/15/2027		220,000	248,598
New Jersey Transportation Trust Fund Authority, Transportation Program, “BB” , 4%, 6/15/2044		1,225,000	1,245,935
			$5,048,057

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Universities - Colleges – 12.2%
Fairmont State University, WV, Board of Governors Rev., “A”, 5%, 6/01/2032	$	4,035,000	$4,129,701
Marshall University, WV, Board of Governors Rev., “A”, AGM, 5%, 5/01/2030		860,000	1,121,251
Marshall University, WV, Board of Governors Rev., “A”, AGM, 4%, 5/01/2050		750,000	841,980
Marshall University, WV, University Rev., 5%, 5/01/2041		1,000,000	1,038,870
Puerto Rico Industrial, Tourist, Educational, Medical & Environmental Control Facilities Financing Authority, Educational Facilities Rev. (University Plaza), “A”, NATL, 5%, 7/01/2021		1,270,000	1,276,807
Puerto Rico Industrial, Tourist, Educational, Medical & Environmental Control Facilities Financing Authority, Higher Education Rev. (Ana G. Mendez University System Project), 5.375%, 12/01/2021		5,000	4,991
Puerto Rico Industrial, Tourist, Educational, Medical & Environmental Control Facilities Financing Authority, Higher Education Rev. (International American University of Puerto Rico Project), 5%, 10/01/2031		110,000	114,935
West Virginia University, Board of Governors Improvement Rev. (West Virginia University Project), “A”, 5%, 10/01/2049		1,000,000	1,238,810
West Virginia University, University Systems Rev., “A”, NATL, 5.25%, 4/01/2028		3,035,000	3,516,442
			$13,283,787
Utilities - Cogeneration – 0.2%
Puerto Rico Industrial, Tourist, Educational, Medical & Environmental Control Facilities Financing Authority Rev. (Cogeneration Facilities - AES Puerto Rico Project), 9.12%, 6/01/2022	$	240,000	$246,000
Utilities - Investor Owned – 0.4%
Michigan Strategic Fund Ltd. Obligation Rev. (Detroit Edison Co.), 5.625%, 7/01/2020	$	470,000	$470,000
Utilities - Municipal Owned – 1.7%
Guam Power Authority Rev., “A”, 5.5%, 10/01/2030 (Prerefunded 10/01/2020)	$	325,000	$329,173
Guam Power Authority Rev., “A”, AGM, 5%, 10/01/2033		435,000	477,334
Puerto Rico Electric Power Authority Rev., “A”, 5%, 7/01/2029 (a)(d)		285,000	198,075
Puerto Rico Electric Power Authority Rev., “A”, 5%, 7/01/2042 (a)(d)		45,000	31,275
Puerto Rico Electric Power Authority Rev., “AAA”, 5.25%, 7/01/2021 (a)(d)		20,000	13,950
Puerto Rico Electric Power Authority Rev., “AAA”, 5.25%, 7/01/2030 (a)(d)		10,000	6,975
Puerto Rico Electric Power Authority Rev., “CCC”, 5.25%, 7/01/2027 (a)(d)		100,000	69,750
Puerto Rico Electric Power Authority Rev., “DDD”, 5%, 7/01/2021 (a)(d)		110,000	76,450
Puerto Rico Electric Power Authority Rev., “DDD”, 5%, 7/01/2021 (a)(d)		10,000	6,950
Puerto Rico Electric Power Authority Rev., “DDD”, 5%, 7/01/2022 (a)(d)		180,000	125,100
Puerto Rico Electric Power Authority Rev., “EEE”, 6.05%, 7/01/2032 (a)(d)		50,000	34,688
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2021 (a)(d)		40,000	27,800
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2023 (a)(d)		50,000	34,750
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2027 (a)(d)		10,000	6,950
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2037 (a)(d)		145,000	100,775
Puerto Rico Electric Power Authority Rev., “VV”, NATL, 5.25%, 7/01/2030		135,000	137,951
Puerto Rico Electric Power Authority Rev., “VV”, NATL, 5.25%, 7/01/2034		10,000	10,208
Puerto Rico Electric Power Authority Rev., “WW”, 5.375%, 7/01/2022 (a)(d)		10,000	6,988
Puerto Rico Electric Power Authority Rev., “WW”, 5.25%, 7/01/2025 (a)(d)		20,000	13,950
Puerto Rico Electric Power Authority Rev., “ZZ”, 5%, 7/01/2022 (a)(d)		70,000	48,475
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2023 (a)(d)		75,000	52,219
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2024 (a)(d)		20,000	13,950
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2026 (a)(d)		65,000	45,337
			$1,869,073
Utilities - Other – 0.7%
Tennessee Energy Acquisition Corp., Gas Rev., “A”, 5.25%, 9/01/2021	$	245,000	$255,172
Tennessee Energy Acquisition Corp., Gas Rev., “A”, 5.25%, 9/01/2022		125,000	134,525
Tennessee Energy Acquisition Corp., Gas Rev., “C”, 5%, 2/01/2021		290,000	295,620
Texas Gas Acquisition & Supply Corp. III., Gas Supply Rev., 5%, 12/15/2031		70,000	74,376
			$759,693
Water & Sewer Utility Revenue – 13.0%
Berkeley County, WV, Public Service Sewer District, “A”, BAM, 5%, 6/01/2036	$	1,700,000	$2,033,523
Fairmont, WV, Waterworks Rev., AAC, 5.25%, 7/01/2022		140,000	146,184
Guam Waterworks Authority Rev. (Water and Wastewater System), 5%, 7/01/2036		40,000	45,564
Guam Waterworks Authority Rev. (Water and Wastewater System), 5%, 1/01/2046		180,000	201,665

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Water & Sewer Utility Revenue – continued
Guam Waterworks Authority Rev. (Water and Wastewater System), “A”, 5%, 7/01/2029	$	20,000	$22,381
Guam Waterworks Authority Rev. (Water and Wastewater System), “A”, 5%, 7/01/2035		20,000	22,025
Guam Waterworks Authority Rev. (Water and Wastewater System), “A”, 5%, 1/01/2050		135,000	161,083
Michigan Finance Authority Local Government Loan Program Rev. (Detroit Water and Sewerage Department Sewage Disposal System Rev. Refunding Second Lien Local Project), “C-7”, NATL, 5%, 7/01/2032		35,000	40,239
Michigan Finance Authority Local Government Loan Program Rev. (Detroit Water and Sewerage Department Water Supply System Rev. Refunding Second Lien Local Project), “D-6”, NATL, 5%, 7/01/2036		40,000	45,417
Michigan Finance Authority Local Government Loan Program Rev. (Detroit Water and Sewerage Department Water Supply System Rev. Refunding Senior Lien Local Project), “D-1”, AGM, 5%, 7/01/2035		20,000	22,509
Michigan Finance Authority Local Government Loan Program Rev. (Detroit Water and Sewerage Department Water Supply System Rev. Refunding Senior Lien Local Project), “D-1”, AGM, 5%, 7/01/2037		50,000	56,047
Mississippi Development Bank Special Obligation (Jackson Water and Sewer System Rev. Bond Project), AGM, 6.875%, 12/01/2040		75,000	88,068
Morgantown, WV, Combined Utility System Rev., “A”, AGM, 5%, 12/01/2041		1,000,000	1,208,310
Morgantown, WV, Combined Utility System Rev., “B”, 5%, 12/01/2043		2,000,000	2,451,320
West Virginia Water Development Authority Rev. (Loan Program II), “A”, 5%, 11/01/2026		650,000	743,665
West Virginia Water Development Authority Rev. (Loan Program II), “A-II”, 5%, 11/01/2033		1,475,000	1,814,073
West Virginia Water Development Authority Rev. (Loan Program IV), “A-IV”, ETM, 5%, 11/01/2038		500,000	619,720
Wheeling, WV, Combined Waterworks and Sewerage System Rev., 5%, 6/01/2038		3,000,000	3,345,570
Wheeling, WV, Combined Waterworks and Sewerage System Rev., 5%, 6/01/2043		1,000,000	1,111,520
			$14,178,883
Total Municipal Bonds			$105,627,270
Bonds – 0.1%
Consumer Services – 0.1%
Toll Road Investors Partnership II LP, Capital Appreciation, NATL, 0%, 2/15/2043 (n)	$	400,000	$119,247
Investment Companies (h) – 1.8%
Money Market Funds – 1.8%
MFS Institutional Money Market Portfolio, 0.17% (v)		1,952,830	$1,953,026

Other Assets, Less Liabilities – 1.5%			1,615,595
Net Assets – 100.0%			$109,315,138

(a)	Non-income producing security.
(d)	In default.
(h)	An affiliated issuer, which may be considered one in which the fund owns 5% or more of the outstanding voting securities, or a company which is under common control. At period end, the aggregate values of the fund's investments in affiliated issuers and in unaffiliated issuers were $1,953,026 and $105,746,517, respectively.
(n)	Securities exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be sold in the ordinary course of business in transactions exempt from registration, normally to qualified institutional buyers. At period end, the aggregate value of these securities was $309,915, representing 0.3% of net assets.
(v)	Affiliated issuer that is available only to investment companies managed by MFS. The rate quoted for the MFS Institutional Money Market Portfolio is the annualized seven-day yield of the fund at period end.

The following abbreviations are used in this report and are defined:
AAC	Ambac Assurance Corp.
AGM	Assured Guaranty Municipal
ASSD GTY	Assured Guaranty Insurance Co.
BAM	Build America Mutual
ETM	Escrowed to Maturity
FHA	Federal Housing Administration
NATL	National Public Finance Guarantee Corp.
VRDN	Variable rate demand note that may be puttable to the issuer at the option of the holder. The stated interest rate, which generally resets either daily or weekly, represents the rate in effect at period end and may not be the current rate.

Portfolio of Investments (unaudited) – continued

Derivative Contracts at 6/30/20
Futures Contracts
Description	Long/ Short	Currency	Contracts	Notional Amount	Expiration Date	Value/Unrealized Appreciation (Depreciation)
Asset Derivatives
Interest Rate Futures
U.S. Treasury Bond	Long	USD	14	$2,499,875	September – 2020	$12,433

At June 30, 2020, the fund had cash collateral of $70,000 to cover any collateral or margin obligations for certain derivative contracts.

See attached supplemental information. For more information see notes to financial statements as disclosed in the most recent semiannual or annual report.

Supplemental Information

6/30/20 (unaudited)

The fund is an investment company and accordingly follows the investment company accounting and reporting guidance of the Financial Accounting Standards Board (FASB) Accounting Standards Codification Topic 946 Financial Services - Investment Companies.

(1) Investment Valuations

Debt instruments and floating rate loans, including restricted debt instruments, are generally valued at an evaluated or composite bid as provided by a third-party pricing service. Short-term instruments with a maturity at issuance of 60 days or less may be valued at amortized cost, which approximates market value. Futures contracts are generally valued at last posted settlement price on their primary exchange as provided by a third-party pricing service. Futures contracts for which there were no trades that day for a particular position are generally valued at the closing bid quotation on their primary exchange as provided by a third-party pricing service. Open-end investment companies are generally valued at net asset value per share. Securities and other assets generally valued on the basis of information from a third-party pricing service may also be valued at a broker/dealer bid quotation. In determining values, third-party pricing services can utilize both transaction data and market information such as yield, quality, coupon rate, maturity, type of issue, trading characteristics, and other market data.

The Board of Trustees has delegated primary responsibility for determining or causing to be determined the value of the fund’s investments (including any fair valuation) to the adviser pursuant to valuation policies and procedures approved by the Board. If the adviser determines that reliable market quotations are not readily available, investments are valued at fair value as determined in good faith by the adviser in accordance with such procedures under the oversight of the Board of Trustees. Under the fund’s valuation policies and procedures, market quotations are not considered to be readily available for most types of debt instruments and floating rate loans and many types of derivatives. These investments are generally valued at fair value based on information from third-party pricing services. In addition, investments may be valued at fair value if the adviser determines that an investment’s value has been materially affected by events occurring after the close of the exchange or market on which the investment is principally traded (such as foreign exchange or market) and prior to the determination of the fund’s net asset value, or after the halt of trading of a specific security where trading does not resume prior to the close of the exchange or market on which the security is principally traded. The adviser generally relies on third-party pricing services or other information (such as the correlation with price movements of similar securities in the same or other markets; the type, cost and investment characteristics of the security; the business and financial condition of the issuer; and trading and other market data) to assist in determining whether to fair value and at what value to fair value an investment. The value of an investment for purposes of calculating the fund’s net asset value can differ depending on the source and method used to determine value. When fair valuation is used, the value of an investment used to determine the fund’s net asset value may differ from quoted or published prices for the same investment. There can be no assurance that the fund could obtain the fair value assigned to an investment if it were to sell the investment at the same time at which the fund determines its net asset value per share.

Various inputs are used in determining the value of the fund's assets or liabilities. These inputs are categorized into three broad levels. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, an investment's level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. The fund's assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the investment. Level 1 includes unadjusted quoted prices in active markets for identical assets or liabilities. Level 2 includes other significant observable market-based inputs (including quoted prices for similar securities, interest rates, prepayment speed, and credit risk). Level 3 includes unobservable inputs, which may include the adviser's own assumptions in determining the fair value of investments. Other financial instruments are derivative instruments, such as futures contracts. The following is a summary of the levels used as of June 30, 2020 in valuing the fund's assets or liabilities:

Financial Instruments	Level 1	Level 2	Level 3	Total
Municipal Bonds	$—	$105,627,270	$—	$105,627,270
U.S. Corporate Bonds	—	119,247	—	119,247
Mutual Funds	1,953,026	—	—	1,953,026
Total	$1,953,026	$105,746,517	$—	$107,699,543
Other Financial Instruments
Futures Contracts – Assets	$12,433	$—	$—	$12,433

For further information regarding security characteristics, see the Portfolio of Investments.

(2) Investments in Affiliated Issuers

An affiliated issuer may be considered one in which the fund owns 5% or more of the outstanding voting securities, or a company which is under common control. For the purposes of this report, the following were affiliated issuers:

Affiliated Issuers	Beginning Value	Purchases	Sales Proceeds	Realized Gain (Loss)	Change in Unrealized Appreciation or Depreciation	Ending Value
MFS Institutional Money Market Portfolio	$781,988	$10,954,135	$9,782,995	$(163)	$61	$1,953,026

Supplemental Information (unaudited) – continued

Affiliated Issuers	Dividend Income	Capital Gain Distributions
MFS Institutional Money Market Portfolio	$1,734	$—

(3) Jurisdiction Weightings

Jurisdiction weighting percentages based on net assets, as of June 30, 2020, are as follows:

West Virginia	68.7%
Puerto Rico	9.5%
New York	2.5%
U.S. Treasury Securities	2.3%
Guam	2.2%
Illinois	1.8%
New Jersey	1.5%
Tennessee	1.2%
California	1.1%
Maryland	1.0%
U.S. Virgin Islands	1.0%
Michigan	0.9%
Alabama	0.8%
North Carolina	0.8%
Ohio	0.8%
South Carolina	0.8%
Texas	0.8%
Florida	0.7%
Massachusetts	0.6%
Virginia	0.6%
Pennsylvania	0.2%
Indiana	0.1%
Mississippi	0.1%
New Hampsire	0.1%

The jurisdiction weighting percentages include both accrued interest amounts and equivalent exposure from any derivatives holdings, if applicable.

(4) Impacts of COVID-19

The pandemic related to the global spread of novel coronavirus disease (COVID-19), which was first detected in December 2019, has resulted in significant disruptions to global business activity and the global economy, as well as the economies of individual countries, the financial performance of individual companies and sectors, and the securities and commodities markets in general. This pandemic, the full effects of which are still unknown, has resulted in substantial market volatility and may have adversely impacted the prices and liquidity of the fund's investments and the fund's performance.