Quarterly Report

December 31, 2023

MFS^® Alabama
Municipal Bond Fund

MAL-Q3

Portfolio of Investments

12/31/23 (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 – 95.8%
Airport Revenue – 0.1%
Denver, CO, City & County Airport System Rev., “A”, 4.125%, 11/15/2047	$	55,000	$54,464
Denver, CO, City & County Airport System Rev., “A”, 4.125%, 11/15/2053		50,000	48,254
			$102,718
General Obligations - General Purpose – 13.5%
Arab, AL, General Obligation Warrants, “A”, AGM, 3%, 12/01/2046	$	1,120,000	$907,006
Birmingham, AL, General Obligation Warrants, “B”, 5%, 12/01/2043		245,000	258,873
Birmingham-Jefferson, AL, Civic Center Authority Rev., “A”, 5.25%, 6/01/2053		750,000	814,659
Bridgeview, IL, Stadium and Redevelopment Projects, Taxable, AAC, 5.14%, 12/01/2036		160,000	143,315
Chicago, IL, General Obligation, “A”, 5.5%, 1/01/2035		40,000	43,582
Chicago, IL, General Obligation, “A”, 5.5%, 1/01/2040		270,000	294,990
Chicago, IL, General Obligation, “F”, 5.5%, 1/01/2042		110,000	110,660
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Capital Appreciation, Series 2022A, 0%, 7/01/2024		5,121	5,021
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Capital Appreciation, Series 2022A, 0%, 7/01/2033		40,508	25,253
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 5.625%, 7/01/2029		34,176	37,066
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 5.75%, 7/01/2031		115,194	128,137
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 4%, 7/01/2033		31,477	30,819
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 4%, 7/01/2035		57,199	55,302
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 4%, 7/01/2037		24,283	23,183
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 4%, 7/01/2041		33,016	30,280
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 4%, 7/01/2046		121,336	108,071
Fort Payne, AL, General Obligation Warrants, “A”, AGM, 5%, 5/01/2047		750,000	775,285
Montevallo, AL, American Village Public Educational Building Authority Refunding Rev. (Alabama Veterans Living Legacy Project), 4%, 12/01/2034		655,000	666,213
Montevallo, AL, American Village Public Educational Building Authority Refunding Rev. (Alabama Veterans Living Legacy Project), 4%, 12/01/2035		250,000	255,056
Oxford, AL, General Obligation Warrants, “A”, 5%, 7/01/2052		1,000,000	1,082,234
Pike Road, AL, General Obligation, 5%, 3/01/2048		500,000	552,746
Pike Road, AL, General Obligation, 5%, 3/01/2052		500,000	549,053
State of Illinois, General Obligation, 5.5%, 5/01/2039		120,000	132,859
State of Illinois, General Obligation, “B”, 5.5%, 5/01/2047		55,000	60,422
Texas Cedar Port Navigation & Improvement District, Unlimited Tax, 4.5%, 9/01/2048		70,000	70,624
Texas Cedar Port Navigation & Improvement District, Unlimited Tax, 4.5%, 9/01/2052		30,000	30,155
Trussville, AL, General Obligation Warrants, “A”, 4%, 8/01/2041		750,000	756,626
Vestavia Hills, AL, General Obligation Warrants, 4%, 8/01/2038		1,000,000	1,023,062
			$8,970,552
General Obligations - Schools – 4.1%
Chicago, IL, Board of Education, Unlimited Tax General Obligation Dedicated Rev., “A”, 4%, 12/01/2047	$	255,000	$221,166
Little Rock, AR, School District & Construction, “A”, BAM, 3%, 2/01/2048		625,000	503,468
Mobile County, AL, Board of School Commissioners, Special Tax School Warrants, 4%, 3/01/2039		1,000,000	1,015,449
Mobile County, AL, Board of School Commissioners, Special Tax School Warrants, “B”, BAM, 4.125%, 3/01/2047		1,000,000	1,002,386
			$2,742,469
Healthcare Revenue - Hospitals – 10.0%
Alabama DCH Health Care Authority, “A”, 4%, 6/01/2046	$	1,000,000	$939,034
Alabama DCH Health Care Authority, Health Care Facilities Rev., 5%, 6/01/2033		500,000	508,923
Alabama Health Care Authority (Baptist Health), “A”, 5%, 11/15/2037		875,000	956,003
Alabama Special Care Facilities Financing Authority Rev. (Daughters of Charity), ETM, AAC, 5%, 11/01/2025		50,000	52,110
Birmingham, AL, Special Care Facilities Financing Authority Health Care Rev. (Children's Hospital), 5%, 6/01/2031		750,000	767,210
Colorado Health Facilities Authority Rev. (CommonSpirit Health), “A-2”, 4%, 8/01/2049		15,000	14,387
East Alabama Health Care Authority, Health Care Facilities Rev., “A”, 4%, 9/01/2048		500,000	477,052
Harris County, TX, Cultural Education Facilities Finance Corp., Hospital Rev. (Memorial Hermann Health System), “A”, 4.125%, 7/01/2052		430,000	412,544
Mobile, AL, Infirmary Health System Special Care Facilities Financing Authority Rev. (Infirmary Health System, Inc.), “A”, 4%, 2/01/2040		1,000,000	968,356

1

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Healthcare Revenue - Hospitals – continued
North Carolina Medical Care Commission, Health Care Facilities Rev. (Rex Healthcare), “A”, 4%, 7/01/2049	$	520,000	$495,117
UAB Medicine Finance Authority Rev., “B”, 5%, 9/01/2035		1,000,000	1,041,327
			$6,632,063
Healthcare Revenue - Long Term Care – 1.8%
Birmingham, AL, Special Care Facilities Financing Authority Rev. (Methodist Home for the Aging), 5.75%, 6/01/2045	$	250,000	$213,119
Pell City, AL, Special Care Facilities Financing Authority Rev. (Noland Health Services, Inc.), “A”, 4%, 12/01/2038		1,000,000	986,643
			$1,199,762
Industrial Revenue - Environmental Services – 0.5%
Muscle Shoals, Sheffield, and Tuscumbia, AL, Solid Waste Disposal Authority Rev. (Cherokee Industrial Landfill Project), “A”, 6%, 5/01/2040 (z)	$	300,000	$325,565
Industrial Revenue - Other – 0.8%
Mobile County, AL, Limited Obligation Warrants (Gomesa Project), 4%, 11/01/2045 (n)	$	500,000	$440,671
Port Beaumont, TX, Navigation District, Dock & Wharf Facility Rev. (Jefferson Gulf Coast Energy Project), “A”, 3.625%, 1/01/2035 (n)		100,000	82,500
			$523,171
Miscellaneous Revenue - Other – 1.7%
Alabama Stadium Trace Village Improvement District Development Incentive Anticipation, 3.625%, 3/01/2036	$	230,000	$188,176
California Infrastructure & Economic Development Bank Rev. (Brightline West Passenger Rail), “A”, VRDN, 3.65%, 1/01/2050 (Put Date 1/31/2024) (n)		375,000	374,589
Matching Fund Special Purpose Securitization Corp., “A”, 5%, 10/01/2026		35,000	35,404
New York Liberty Development Corp., Liberty Rev. (3 World Trade Center Project), “1”, 5%, 11/15/2044 (n)		260,000	257,657
Pennsylvania Economic Development Financing Authority, Private Activity Rev. (PennDOT Major Bridges Package One Project), AGM, 5%, 12/31/2057		275,000	283,845
			$1,139,671
Multi-Family Housing Revenue – 2.8%
Alabama Housing Finance Authority, Multi-Family Housing Rev. (Maryvale Place Project), “F”, HUD Section 8, 4%, 10/01/2025 (Put Date 4/01/2025)	$	1,000,000	$1,003,590
National Finance Authority, NH, Municipal Certificates, “1-A”, 4.375%, 9/20/2036		219,689	221,886
New Mexico Mortgage Finance Authority, Multifamily Housing Rev. (Mountain View II & III Apartments Project), HUD Section 8, 5%, 2/01/2042 (Put Date 9/01/2025)		75,000	76,412
New Mexico Mortgage Finance Authority, Multifamily Housing Rev. (Santa Fe Apartment & Sangre de Cristo Project), HUD Section 8, 5%, 2/01/2042 (Put Date 6/01/2025)		120,000	121,193
New York, NY, Housing Development Corp., Multi-Family Housing Rev. (Sustainable Development Bonds), “G”, FHA, 2.45%, 11/01/2045		585,000	424,641
			$1,847,722
Port Revenue – 1.6%
Alabama Port Authority Docks Facilities Refunding Rev., “A”, AGM, 5%, 10/01/2035	$	1,000,000	$1,043,158
Sales & Excise Tax Revenue – 9.5%
Cherokee County, AL, Board of Education Special Tax School Warrants (Sales Tax), 5%, 12/01/2048	$	1,000,000	$1,051,202
Chicago, IL, Metropolitan Pier & Exposition Authority Refunding Bonds (McCormick Place Expansion Project), Capital Appreciation, “B-1”, AGM, 0%, 6/15/2044		820,000	346,864
Guam Government Business Privilege Tax Refunding, “F”, 5%, 1/01/2030		5,000	5,385
Guam Government Business Privilege Tax Refunding, “F”, 5%, 1/01/2031		5,000	5,421
Guam Government Business Privilege Tax Refunding, “F”, 4%, 1/01/2042		60,000	57,439
Jefferson County, AL, Cooper Green Mercy Health Services Authority Rev., “A”, 5.25%, 9/01/2052		810,000	854,378
Jefferson County, AL, Limited Obligation Refunding Warrants, 4%, 9/15/2042		1,000,000	1,003,703
Lawrence County, AL, Board of Education Special Tax School Warrants, AGM, 4%, 2/01/2042		1,000,000	1,024,925
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-1”, 4.55%, 7/01/2040		16,000	16,078
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-1”, 4.75%, 7/01/2053		57,000	56,410
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-1”, 5%, 7/01/2058		796,000	798,778
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.329%, 7/01/2040		142,000	140,965
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.329%, 7/01/2040		58,000	57,577

2

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Sales & Excise Tax Revenue – continued
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.784%, 7/01/2058	$	401,000	$395,262
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2027		26,000	22,630
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2029		4,000	3,199
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2031		247,000	180,773
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2033		237,000	157,857
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2046		110,000	34,488
Wisconsin Public Finance Authority Limited Obligation Grant Rev. (American Dream at Meadowlands Project), “A”, 6.25%, 8/01/2027 (a)(d)(n)		100,000	78,000
			$6,291,334
Single Family Housing - State – 0.9%
Connecticut Housing Finance Authority Rev. (Housing Mortgage Finance Program), “C-1”, 4%, 11/15/2047	$	110,000	$109,681
Maryland Community Development Administration, Department of Housing & Community Development Residential Rev., “A”, GNMA, 4.45%, 9/01/2043		385,000	391,592
Maryland Community Development Administration, Department of Housing & Community Development Residential Rev., “A”, GNMA, 4.5%, 9/01/2046		130,000	131,808
			$633,081
State & Local Agencies – 1.3%
Alabama Public Health Care Authority Lease Rev. (Department of Public Health Facilities), 5%, 9/01/2030	$	280,000	$286,296
Bessemer, AL, Public Educational Building Authority Rev. (DHR Building Project), “A”, AGM, 5%, 7/01/2030		210,000	210,273
Pennsylvania Public School Building Authority, School Lease Rev. (School District of Philadelphia Project), “A”, AGM, 5%, 6/01/2033		350,000	368,058
			$864,627
Student Loan Revenue – 0.8%
Iowa Student Loan Liquidity Corp. Rev., “B”, 3%, 12/01/2039	$	5,000	$4,825
Iowa Student Loan Liquidity Corp. Rev., “C”, 3.5%, 12/01/2044		90,000	75,274
Minnesota Office of Higher Education Supplemental Student Loan Program Rev., 2.65%, 11/01/2038		40,000	35,914
New Jersey Higher Education Student Assistance Authority, Senior Student Loan Rev., “B”, 4%, 12/01/2041		415,000	409,817
			$525,830
Tax - Other – 5.9%
Birmingham-Jefferson, AL, Civic Center Authority, “A”, 4%, 7/01/2043	$	750,000	$752,161
Chicago, IL, Board of Education, Dedicated Capital Improvement Tax Bond, 5%, 4/01/2045		45,000	46,960
Chicago, IL, Board of Education, Dedicated Capital Improvement Tax Bond, 5.75%, 4/01/2048		125,000	136,701
Guam Government Limited Obligation Rev., “A”, 5%, 12/01/2036		30,000	30,731
Guam Government Limited Obligation Rev., “A”, 5%, 12/01/2046		85,000	84,733
Jefferson County, AL, Board of Education, 4%, 2/01/2042		805,000	809,367
St. Clair County, AL, Board of Education, Special Tax School Warrants (15 Mill Moody Tax), “A”, BAM, 4.125%, 2/01/2048		500,000	504,510
St. Clair County, AL, Board of Education, Special Tax School Warrants (15 Mill Moody Tax), “A”, BAM, 4.25%, 2/01/2052		500,000	508,071
Tuscaloosa, AL, Board of Education, School Tax Warrants, 5%, 8/01/2036 (Prerefunded 8/01/2026)		1,000,000	1,059,426
			$3,932,660
Tobacco – 0.6%
Buckeye, OH, Tobacco Settlement Financing Authority Senior Asset-Backed Refunding, 2020B-2, “2”, 5%, 6/01/2055	$	185,000	$173,855
Golden State, CA, Tobacco Securitization Corp., Tobacco Settlement Rev., Taxable, “B-1”, 3.85%, 6/01/2050		250,000	231,247
			$405,102
Toll Roads – 0.3%
Virginia Small Business Financing Authority Senior Lien Rev. (Elizabeth River Crossings Opco LLC Project), 3%, 1/01/2041	$	250,000	$205,069
Transportation - Special Tax – 3.5%
Jefferson County, AL, Transportation Infrastructure Bank, Limited Obligation Rev., “B”, AGM, 5%, 8/15/2035	$	1,000,000	$1,143,777
Jefferson County, AL, Transportation Infrastructure Bank, Limited Obligation Rev., “B”, AGM, 5%, 8/15/2036		1,000,000	1,135,624
New Jersey Transportation Trust Fund Authority, “CC”, 5.5%, 6/15/2050		40,000	44,790
			$2,324,191

3

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Universities - Colleges – 13.3%
Alabama Community College System Board of Trustees Rev. (Bishop State Community College), BAM, 4%, 1/01/2044	$	300,000	$297,561
Alabama Community College System Board of Trustees Rev. (Bishop State Community College), BAM, 4%, 1/01/2049		1,000,000	952,062
Alabama Community College System Board of Trustees Rev. (Gadsden State Community College), AGM, 5%, 6/01/2048		500,000	530,228
Alabama Community College System Board of Trustees Rev. (Gadsden State Community College), AGM, 5%, 6/01/2053		500,000	527,492
Auburn University, AL, General Fee Rev., “A”, 5%, 6/01/2048		1,500,000	1,582,104
Homewood, AL, Educational Building Authority Facilities Rev. (Samford University), “A”, 5%, 12/01/2034		500,000	522,882
Jacksonville, AL, Public Educational Building Authority Higher Education Facilities Rev. (Jacksonville State University Foundation), “A”, 5%, 7/01/2036		580,000	602,143
Jacksonville, AL, Public Educational Building Authority Higher Education Facilities Rev. (Jacksonville State University Foundation), “A”, AGM, 5.25%, 8/01/2048		750,000	822,516
Massachusetts Development Finance Agency Rev. (Suffolk University), 4%, 7/01/2051		345,000	290,085
Puerto Rico Industrial, Tourist, Educational, Medical & Environmental Control Facilities Financing Authority, Educational Facilities Rev. (University Plaza Project), NPFG, 5%, 7/01/2033		60,000	58,697
University of North Alabama, General Fee Rev., “B”, BAM, 5%, 11/01/2039		1,000,000	1,086,279
University of South Alabama, Facilities Rev., “A”, BAM, 5%, 4/01/2049		750,000	782,478
University of West Alabama, General Fee Rev., AGM, 4%, 1/01/2040		770,000	775,792
			$8,830,319
Utilities - Investor Owned – 0.7%
Mobile, AL, Industrial Development Board Pollution Control Rev. (Alabama Power Co. Barry Plant Project), “C”, 3.78%, 6/01/2034 (Put Date 6/16/2026)	$	500,000	$504,639
Utilities - Municipal Owned – 0.6%
Puerto Rico Electric Power Authority Refunding Rev., “DDD”, 5%, 7/01/2020 (a)(d)	$	5,000	$1,300
Puerto Rico Electric Power Authority Refunding Rev., “DDD”, 5%, 7/01/2021 (a)(d)		70,000	18,200
Puerto Rico Electric Power Authority Refunding Rev., “DDD”, 5%, 7/01/2022 (a)(d)		115,000	29,900
Puerto Rico Electric Power Authority Refunding Rev., “VV”, NPFG, 5.25%, 7/01/2034		15,000	14,786
Puerto Rico Electric Power Authority Rev., “A”, 5%, 7/01/2029 (a)(d)		180,000	46,800
Puerto Rico Electric Power Authority Rev., “A”, 5%, 7/01/2042 (a)(d)		30,000	7,800
Puerto Rico Electric Power Authority Rev., “AAA”, 5.25%, 7/01/2021 (a)(d)		15,000	3,900
Puerto Rico Electric Power Authority Rev., “AAA”, 5.25%, 7/01/2030 (a)(d)		5,000	1,300
Puerto Rico Electric Power Authority Rev., “CCC”, 5.25%, 7/01/2027 (a)(d)		65,000	16,900
Puerto Rico Electric Power Authority Rev., “DDD”, AGM, 3.65%, 7/01/2024		50,000	49,644
Puerto Rico Electric Power Authority Rev., “SS”, AGM, 4.375%, 7/01/2030		15,000	14,439
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2021 (a)(d)		40,000	10,400
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2023 (a)(d)		30,000	7,800
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2027 (a)(d)		5,000	1,300
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2037 (a)(d)		95,000	24,700
Puerto Rico Electric Power Authority Rev., “UU”, AGM, 4.25%, 7/01/2027		70,000	68,207
Puerto Rico Electric Power Authority Rev., “WW”, 5.375%, 7/01/2022 (a)(d)		5,000	1,300
Puerto Rico Electric Power Authority Rev., “WW”, 5.25%, 7/01/2025 (a)(d)		15,000	3,900
Puerto Rico Electric Power Authority Rev., “ZZ”, 5%, 7/01/2018 (a)(d)		40,000	10,400
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2023 (a)(d)		50,000	13,000
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2024 (a)(d)		15,000	3,900
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2026 (a)(d)		55,000	14,300
Puerto Rico Electric Power Authority Rev., Taxable, “EEE”, 6.05%, 7/01/2032 (a)(d)		40,000	9,700
			$373,876
Utilities - Other – 4.8%
Black Belt Energy Gas District, AL, Gas Project Rev. (Project No. 8), “A”, 4%, 12/01/2052 (Put Date 12/01/2029)	$	180,000	$177,428
Black Belt Energy Gas District, AL, Gas Project Rev., “A”, 4%, 6/01/2051 (Put Date 12/01/2031)		210,000	211,475
Black Belt Energy Gas District, AL, Gas Project Rev., “C-1”, 5.25%, 2/01/2053 (Put Date 6/01/2029)		425,000	453,835
California Community Choice Financing Authority, Clean Energy Project Rev., “C”, 5.25%, 1/01/2054 (Put Date 10/01/2031)		410,000	433,707
Public Energy Authority of Kentucky, Gas Supply Rev., “A-1”, 4%, 8/01/2052 (Put Date 8/01/2030)		1,000,000	1,003,681
Southeast Alabama Energy Authority Commodity Supply Rev. (Project No. 5), “A”, 5.25%, 1/01/2054 (Put Date 7/01/2029)		360,000	383,110
Southeast Alabama Energy Authority Commodity Supply Rev. (Project No.6), 5%, 1/01/2054 (Put Date 6/01/2030)		500,000	533,664
			$3,196,900

4

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Water & Sewer Utility Revenue – 16.7%
Auburn, AL, Waterworks Board Water Rev., 5%, 9/01/2036 (Prerefunded 9/01/2025)	$	1,000,000	$1,035,139
Baldwin County, AL, Solid Waste Disposal Authority Rev., 4.25%, 12/01/2048		500,000	500,580
Baldwin County, AL, Solid Waste Disposal Authority Rev., 4.375%, 12/01/2053		500,000	500,008
Birmingham, AL, Water Rev., 5%, 1/01/2038		500,000	578,040
Birmingham, AL, Water Rev., 5%, 1/01/2039		250,000	286,646
Cullman, AL, Utilities Board Water Rev., “A”, AGM, 5%, 9/01/2035		1,000,000	1,011,672
Gadsden, AL, Waterworks and Sewer Rev., AGM, 4%, 6/01/2033		1,000,000	1,029,338
Guam Waterworks Authority Rev. (Water and Wastewater System), 5%, 7/01/2036		45,000	46,412
Guam Waterworks Authority Rev. (Water and Wastewater System), 5%, 1/01/2046		120,000	121,816
Guam Waterworks Authority Rev. (Water and Wastewater System), “A”, 5%, 7/01/2029		45,000	45,361
Guam Waterworks Authority Rev. (Water and Wastewater System), “A”, 5%, 7/01/2035		45,000	45,326
Guam Waterworks Authority Rev. (Water and Wastewater System), “A”, 5%, 1/01/2050		95,000	97,777
Jefferson County, AL, Senior Lien Sewer Rev., Current Interest Warrants, “A”, AGM, 5%, 10/01/2044		750,000	760,678
Limestone County, AL, Water & Sewer Authority Rev., 5%, 12/01/2045		1,000,000	1,089,514
Madison, AL, Water & Wastewater Board Rev., 3%, 12/01/2050		1,000,000	778,704
Michigan Finance Authority Local Government Loan Program Rev. (Detroit Water and Sewerage Department Sewage Disposal System Rev. Refunding Second Lien Local Project), “C-7”, NPFG, 5%, 7/01/2032		15,000	15,082
Michigan Finance Authority Local Government Loan Program Rev. (Detroit Water and Sewerage Department Water Supply System Rev. Refunding Second Lien Local Project), “D-6”, NPFG, 5%, 7/01/2036		20,000	20,086
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		20,000	20,077
Montgomery, AL, Water Works and Sanitary Sewer Board, Water and Sewer Rev., 5%, 9/01/2048		500,000	553,156
Orange Beach, AL, Water Sewer & Fire Protection Authority Water Rev., 4%, 5/15/2047		1,000,000	999,985
Prattville, AL Water Works Board Rev., 5.125%, 8/01/2053		750,000	819,412
Prichard, AL, Water Works & Sewer Board Rev., 4%, 11/01/2044		700,000	508,773
Texas Water Development Board State Water Implementation Rev., “A”, 5%, 10/15/2058		200,000	221,266
			$11,084,848
Total Municipal Bonds			$63,699,327
Bonds – 0.3%
Consumer Services – 0.3%
Toll Road Investors Partnership II LP, Capital Appreciation, NPFG, 0%, 2/15/2025 (n)	$	136,000	$125,843
Toll Road Investors Partnership II LP, Capital Appreciation, NPFG, 0%, 2/15/2043 (n)		189,099	60,151
Total Bonds			$185,994
Contingent Value Instruments – 0.1%
General Obligations - General Purpose – 0.1%
Commonwealth of Puerto Rico, General Obligation Contingent Value Instrument, 11/01/2043	$	139,526	$76,042
Investment Companies (h) – 3.0%
Money Market Funds – 3.0%
MFS Institutional Money Market Portfolio, 5.42% (v)		1,986,785	$1,987,182
Other Assets, Less Liabilities – 0.8%			514,185
Net Assets – 100.0%			$66,462,730

(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 $1,987,182 and $63,961,363, 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 $1,419,411, representing 2.1% 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.

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Portfolio of Investments (unaudited) – continued

(z) Restricted securities are not registered under the Securities Act of 1933 and are subject to legal restrictions on resale. These securities generally may be resold in transactions exempt from registration or to the public if the securities are subsequently registered. Disposal of these securities may involve time-consuming negotiations and prompt sale at an acceptable price may be difficult. The fund holds the following restricted securities:

Restricted Securities	Acquisition Date	Cost	Value
Muscle Shoals, Sheffield, and Tuscumbia, AL, Solid Waste Disposal Authority Rev. (Cherokee Industrial Landfill Project), “A”, 6%, 5/01/2040	6/10/2020	$310,382	$325,565
% of Net assets			0.5%

The following abbreviations are used in this report and are defined:
AAC	Ambac Assurance Corp.
AGM	Assured Guaranty Municipal
BAM	Build America Mutual
ETM	Escrowed to Maturity
FHA	Federal Housing Administration
GNMA	Government National Mortgage Assn.
NPFG	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.

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

6

Supplemental Information

12/31/23 (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

Subject to its oversight, the fund's Board of Trustees has delegated primary responsibility for determining or causing to be determined the value of the fund’s investments to MFS as the fund's adviser, pursuant to the fund’s valuation policy and procedures which have been adopted by the adviser and approved by the Board. In accordance with Rule 2a-5 under the Investment Company Act of 1940, the Board of Trustees designated the adviser as the “valuation designee” of the fund. If the adviser, as valuation designee, determines that reliable market quotations are not readily available for an investment, the investment is valued at fair value as determined in good faith by the adviser in accordance with the adviser’s fair valuation policy and procedures.

Under the fund's valuation policy and procedures, 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. Open-end investment companies are generally valued at net asset value per share.

Under the fund’s valuation policy and procedures, market quotations are not considered to be readily available for debt instruments, floating rate loans, and many types of derivatives. These investments are generally valued at fair value based on information from third-party pricing services or otherwise determined by the adviser in accordance with the adviser’s fair valuation policy and procedures. 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, spreads and other market data. An investment may also be valued at fair value if the adviser determines that the 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 significant unobservable inputs, which may include the adviser's own assumptions in determining the fair value of investments. The following is a summary of the levels used as of December 31, 2023 in valuing the fund's assets and liabilities:

Financial Instruments	Level 1	Level 2	Level 3	Total
Municipal Bonds	$—	$63,775,369	$—	$63,775,369
U.S. Corporate Bonds	—	185,994	—	185,994
Mutual Funds	1,987,182	—	—	1,987,182
Total	$1,987,182	$63,961,363	$—	$65,948,545

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	$1,420,478	$18,277,130	$17,709,866	$(499)	$(61)	$1,987,182

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Supplemental Information (unaudited) – continued

Affiliated Issuers	Dividend Income	Capital Gain Distributions
MFS Institutional Money Market Portfolio	$54,548	$—

(3) Jurisdiction Weightings

Jurisdiction weighting percentages based on net assets, as of December 31, 2023, are as follows:

Alabama	77.8%
Puerto Rico	4.3%
Illinois	2.3%
California	1.6%
Kentucky	1.5%
Texas	1.3%
New York	1.0%
Pennsylvania	1.0%
Arkansas	0.8%
Guam	0.8%
Maryland	0.8%
North Carolina	0.8%
New Jersey	0.7%
Virginia	0.6%
Massachusetts	0.4%
New Hampshire	0.3%
New Mexico	0.3%
Ohio	0.3%
Colorado	0.2%
Connecticut	0.2%
Iowa	0.1%
Michigan	0.1%
Minnesota	0.1%
U.S. Virgin Islands	0.1%
Wisconsin	0.1%

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

8