Quarterly Report

December 31, 2023

MFS^® Massachusetts
Municipal Bond Fund

MMA-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 – 96.2%
Airport Revenue – 5.9%
Denver, CO, City & County Airport System Rev., “A”, 4.125%, 11/15/2047	$	265,000	$262,419
Denver, CO, City & County Airport System Rev., “A”, 4.125%, 11/15/2053		250,000	241,268
Massachusetts Port Authority Rev., “A”, 5%, 7/01/2038		2,000,000	2,141,491
Massachusetts Port Authority Rev., “A”, 5%, 7/01/2040		2,755,000	2,927,675
Massachusetts Port Authority Rev., “A”, 5%, 7/01/2042		3,000,000	3,101,447
Massachusetts Port Authority Rev., “A”, 5%, 7/01/2042		3,455,000	3,739,429
Massachusetts Port Authority Rev., “A”, 5%, 7/01/2047		1,500,000	1,539,129
Massachusetts Port Authority Rev., “C”, 5%, 7/01/2044		3,000,000	3,146,397
Massachusetts Port Authority Rev., “E”, 5%, 7/01/2051		3,055,000	3,201,627
			$20,300,882
General Obligations - General Purpose – 12.4%
Bridgeview, IL, Stadium and Redevelopment Projects, Taxable, AAC, 5.14%, 12/01/2036	$	705,000	$631,482
Brockton, MA, Public Safety Facility, General Obligation, 4%, 8/01/2052		2,000,000	1,987,974
Commonwealth of Massachusetts, “B”, 5.25%, 8/01/2028		2,225,000	2,512,777
Commonwealth of Massachusetts, General Obligation Consolidated Loan, “C”, 5%, 5/01/2029		1,410,000	1,411,188
Commonwealth of Massachusetts, General Obligation Consolidated Loan, “F”, 5%, 11/01/2042		3,000,000	3,159,287
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Capital Appreciation, Series 2022A, 0%, 7/01/2024		23,374	22,915
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Capital Appreciation, Series 2022A, 0%, 7/01/2033		184,909	115,275
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 5.625%, 7/01/2029		156,003	169,197
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 5.75%, 7/01/2031		343,525	382,122
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 4%, 7/01/2033		143,685	140,682
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 4%, 7/01/2035		282,284	272,924
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 4%, 7/01/2037		110,848	105,828
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 4%, 7/01/2041		150,711	138,223
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Series 2022A, 4%, 7/01/2046		516,737	460,243
Framingham, MA, General Obligation Purpose Loan, 5%, 8/01/2041		1,095,000	1,233,941
Framingham, MA, General Obligation Purpose Loan, 5%, 8/01/2042		1,130,000	1,265,533
Lawrence, MA, General Obligation Purpose Loan, 4%, 6/01/2034		1,125,000	1,229,921
Lawrence, MA, General Obligation Purpose Loan, 4%, 6/01/2044		1,665,000	1,691,482
Lawrence, MA, General Obligation Purpose Loan, 3%, 2/01/2049		3,000,000	2,417,970
Nantucket, MA, General Obligation Purpose Loan, “A”, 4%, 8/15/2039		1,090,000	1,159,293
Nantucket, MA, General Obligation Purpose Loan, “A”, 4%, 8/15/2040		1,125,000	1,187,104
Nantucket, MA, General Obligation Purpose Loan, “A”, 4%, 8/15/2041		1,000,000	1,047,643
Nantucket, MA, General Obligation Purpose Loan, “A”, 4%, 8/15/2042		695,000	723,025
New Bedford, MA, General Obligation State Qualified Municipal Purpose Loan, 4%, 9/01/2047		5,000,000	5,009,722
Norton, MA, General Obligation Municipal Purpose Loan, 5%, 10/15/2025		350,000	364,885
Pittsfield, MA, General Obligation State Qualified Municipal Purpose Loan, 4%, 12/01/2041		685,000	709,078
Pittsfield, MA, General Obligation State Qualified Municipal Purpose Loan, 4%, 12/01/2042		790,000	811,331
Pittsfield, MA, General Obligation State Qualified Municipal Purpose Loan, 4%, 12/01/2043		730,000	747,431
Provincetown, MA, General Obligation Municipal Purpose Loan, Taxable, 3%, 6/15/2028		755,000	755,704
Quincy, MA, General Obligation, “B”, 5%, 7/01/2038		675,000	782,119
Quincy, MA, General Obligation, “B”, 5%, 7/01/2039		740,000	849,794
Quincy, MA, General Obligation, “B”, 5%, 7/01/2040		785,000	895,143
Quincy, MA, General Obligation, “B”, 5%, 7/01/2041		620,000	704,042
Quincy, MA, General Obligation, “B”, 5%, 7/01/2042		600,000	678,140
State of Illinois, General Obligation, 5.5%, 5/01/2039		280,000	310,004
State of Illinois, General Obligation, 5.75%, 5/01/2045		255,000	280,638
State of Illinois, General Obligation, “C”, 4%, 10/01/2040		950,000	951,677
State of Illinois, General Obligation, “C”, 4%, 10/01/2041		595,000	592,892
Texas Cedar Port Navigation & Improvement District, Unlimited Tax, 4.5%, 9/01/2048		395,000	398,521
Texas Cedar Port Navigation & Improvement District, Unlimited Tax, 4.5%, 9/01/2052		160,000	160,824
Tisbury, MA, General Obligation, Municipal Purpose Loan, Unlimited Tax, 3%, 8/15/2052		5,000,000	4,081,633
			$42,549,607

1

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
General Obligations - Schools – 2.9%
Bristol-Plymouth Regional Vocational Technical School District, MA, 5%, 2/28/2024	$	6,000,000	$6,012,879
Chicago, IL, Board of Education, Unlimited Tax General Obligation Dedicated Rev., “A”, 4%, 12/01/2047		1,270,000	1,101,495
Orange County, CA, Anaheim Elementary School District, AGM, 4%, 8/01/2048		1,285,000	1,291,411
San Marcos, CA, Unified School District (Election of 2010), Capital Appreciation, “C”, 0%, 8/01/2038 (Prerefunded 2/15/2024)		3,375,000	1,576,266
			$9,982,051
Healthcare Revenue - Hospitals – 15.2%
California Health Facilities Financing Authority Rev. (Cedars-Sinai Health System), “A”, 5%, 8/15/2051	$	2,405,000	$2,649,616
Harris County, TX, Cultural Education Facilities Finance Corp., Hospital Rev. (Memorial Hermann Health System), “A”, 4.125%, 7/01/2052		1,960,000	1,880,435
Massachusetts Development Finance Agency Rev. (Atrius Health Issue), “A”, 4%, 6/01/2049 (Prerefunded 6/01/2029)		1,500,000	1,621,017
Massachusetts Development Finance Agency Rev. (Baystate Medical Center), “N”, 5%, 7/01/2044		2,000,000	2,008,403
Massachusetts Development Finance Agency Rev. (Beth Israel Lahey Health, Inc.), “J-2”, 5%, 7/01/2043		2,855,000	2,983,669
Massachusetts Development Finance Agency Rev. (Beth Israel Lahey Health, Inc.), “J-2”, 5%, 7/01/2048		3,615,000	3,743,161
Massachusetts Development Finance Agency Rev. (Beth Israel Lahey Health, Inc.), “K”, 5%, 7/01/2036		635,000	689,753
Massachusetts Development Finance Agency Rev. (Beth Israel Lahey Health, Inc.), “K”, 5%, 7/01/2037		850,000	917,183
Massachusetts Development Finance Agency Rev. (Beth Israel Lahey Health, Inc.), “K”, 5%, 7/01/2038		700,000	749,541
Massachusetts Development Finance Agency Rev. (Boston Medical Center), “G”, 5.25%, 7/01/2048		2,000,000	2,188,413
Massachusetts Development Finance Agency Rev. (CareGroup), “I”, 5%, 7/01/2037		1,000,000	1,032,988
Massachusetts Development Finance Agency Rev. (CareGroup), “J-2”, 5%, 7/01/2036		1,000,000	1,072,087
Massachusetts Development Finance Agency Rev. (CareGroup), “J-2”, 5%, 7/01/2037		1,000,000	1,066,154
Massachusetts Development Finance Agency Rev. (Children's Hospital), “P”, 5%, 10/01/2032 (Prerefunded 10/01/2024)		1,000,000	1,015,740
Massachusetts Development Finance Agency Rev. (Dana-Farber Cancer Institute), “N”, 5%, 12/01/2041		1,690,000	1,748,977
Massachusetts Development Finance Agency Rev. (Dana-Farber Cancer Institute), “O”, 5%, 12/01/2034		400,000	442,747
Massachusetts Development Finance Agency Rev. (Lahey Health System), “F”, 5%, 8/15/2030		2,000,000	2,045,425
Massachusetts Development Finance Agency Rev. (Milford Regional Medical Center), “F”, 5.75%, 7/15/2043		1,000,000	1,000,120
Massachusetts Development Finance Agency Rev. (Milford Regional Medical Center), “G”, 5%, 7/15/2046 (n)		1,000,000	914,989
Massachusetts Development Finance Agency Rev. (Partners Healthcare), “Q”, 5%, 7/01/2041		1,810,000	1,865,012
Massachusetts Development Finance Agency Rev. (Partners Healthcare), “Q”, 5%, 7/01/2047		1,500,000	1,538,085
Massachusetts Development Finance Agency Rev. (Partners Healthcare), “S”, 4%, 7/01/2041		1,500,000	1,508,641
Massachusetts Development Finance Agency Rev. (South Shore Hospital), “I”, 5%, 7/01/2041		2,300,000	2,329,150
Massachusetts Development Finance Agency Rev. (UMass Memorial Health Care Obligated Group), “I”, 5%, 7/01/2041		1,850,000	1,885,254
Massachusetts Development Finance Agency Rev. (UMass Memorial Health Care Obligated Group), “K”, 5%, 7/01/2038		2,000,000	2,054,745
Massachusetts Development Finance Agency Rev. (UMass Memorial Health Care Obligated Group), “L”, 5%, 7/01/2044		1,000,000	1,018,531
Massachusetts Development Finance Agency Rev. (Wellforce, Inc.), “A”, 4%, 7/01/2044		2,080,000	1,894,428
Massachusetts Development Finance Agency Rev. (Wellforce, Inc.), “A”, 5%, 7/01/2044		2,000,000	1,961,851
Massachusetts Development Finance Agency Rev. (Wellforce, Inc.), “C”, AGM, 4%, 10/01/2045		4,150,000	3,909,321
New York Dormitory Authority Rev. (Norwell Health Obligated Group), “A”, 4.25%, 5/01/2052		2,120,000	2,120,053
			$51,855,489
Healthcare Revenue - Long Term Care – 1.3%
Massachusetts Development Finance Agency First Mortgage Rev. (Berkshire Retirement Community), 5%, 7/01/2031	$	1,000,000	$1,016,068
Massachusetts Development Finance Agency Rev. (Adventcare), “A”, 6.75%, 10/15/2037 (a)(d)		415,361	4,154
Massachusetts Development Finance Agency Rev. (Carleton-Willard Village), 4%, 12/01/2042		485,000	444,792
Massachusetts Development Finance Agency Rev. (Carleton-Willard Village), 5%, 12/01/2042		525,000	535,173
Massachusetts Development Finance Agency Rev. (Loomis Communities), 4%, 1/01/2031 (n)		500,000	497,285
Massachusetts Development Finance Agency Rev. (Loomis Communities), 4%, 1/01/2051		900,000	753,415
Massachusetts Development Finance Agency Rev. (Newbridge on the Charles, Inc.), 5%, 10/01/2037 (n)		1,250,000	1,238,876
			$4,489,763
Industrial Revenue - Environmental Services – 0.4%
California Municipal Finance Authority, Solid Waste Disposal Rev. (Waste Management, Inc. Project), “A”, 4.25%, 12/01/2044 (Put Date 12/02/2024)	$	1,165,000	$1,167,035
Industrial Revenue - Other – 0.1%
Port Beaumont, TX, Navigation District, Dock & Wharf Facility Rev. (Jefferson Gulf Coast Energy Project), “A”, 3.625%, 1/01/2035 (n)	$	500,000	$412,499

2

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Miscellaneous Revenue - Other – 3.3%
California Infrastructure & Economic Development Bank Rev. (Brightline West Passenger Rail), “A”, VRDN, 3.65%, 1/01/2050 (Put Date 1/31/2024) (n)	$	2,235,000	$2,232,551
Massachusetts Development Finance Agency Rev. (Woods Hole Oceanographic Institution), 5%, 6/01/2037		1,000,000	1,078,476
Massachusetts Development Finance Agency Rev. (Woods Hole Oceanographic Institution), 5%, 6/01/2038		1,000,000	1,071,466
Massachusetts Development Finance Agency Rev. (Woods Hole Oceanographic Institution), 5%, 6/01/2043		1,000,000	1,060,230
Massachusetts Port Authority Special Facilities Rev. (BOSFuel Project), “A”, 5%, 7/01/2038		1,180,000	1,251,391
Massachusetts Port Authority Special Facilities Rev. (BOSFuel Project), “A”, 5%, 7/01/2039		2,000,000	2,112,146
Matching Fund Special Purpose Securitization Corp., “A”, 5%, 10/01/2026		140,000	141,615
New York Liberty Development Corp., Liberty Rev. (3 World Trade Center Project), “1”, 5%, 11/15/2044 (n)		950,000	941,440
Pennsylvania Economic Development Financing Authority, Private Activity Rev. (PennDOT Major Bridges Package One Project), AGM, 5%, 12/31/2057		1,495,000	1,543,087
			$11,432,402
Multi-Family Housing Revenue – 5.7%
Massachusetts Housing Finance Agency, “A”, 3.7%, 12/01/2038	$	1,000,000	$995,056
Massachusetts Housing Finance Agency, “A”, 3.8%, 12/01/2043		2,025,000	1,976,270
Massachusetts Housing Finance Agency, “C”, 5.35%, 12/01/2049		1,035,000	1,035,344
Massachusetts Housing Finance Agency, “C-1”, 5.1%, 12/01/2048		1,000,000	1,051,469
Massachusetts Housing Finance Agency, “C-1”, 5.2%, 12/01/2053		1,000,000	1,055,815
Massachusetts Housing Finance Agency, “C-1”, HUD Section 8, 4.85%, 12/01/2043		1,000,000	1,040,367
Massachusetts Housing Finance Agency, “C-1”, HUD Section 8, 5.125%, 12/01/2057		3,000,000	3,180,772
Massachusetts Housing Finance Agency, “A-3”, 3.05%, 12/01/2027		3,000,000	2,995,871
Massachusetts Housing Finance Agency, “C-1”, 2.9%, 12/01/2039		1,000,000	859,927
Massachusetts Housing Finance Agency, “C-1”, 3.1%, 12/01/2044		2,000,000	1,633,098
Massachusetts Housing Finance Agency, Multi-Family Housing, “A”, FHA, 4.75%, 12/01/2030		1,425,000	1,426,025
Massachusetts Housing Finance Agency, Multi-Family Housing, “A”, FHA, 4.875%, 12/01/2032		1,190,000	1,190,826
National Finance Authority, NH, Municipal Certificates, “1-A”, 4.375%, 9/20/2036		1,102,858	1,113,883
			$19,554,723
Sales & Excise Tax Revenue – 5.5%
Guam Government Business Privilege Tax Refunding, “F”, 5%, 1/01/2030	$	20,000	$21,538
Guam Government Business Privilege Tax Refunding, “F”, 5%, 1/01/2031		25,000	27,107
Guam Government Business Privilege Tax Refunding, “F”, 4%, 1/01/2042		255,000	244,116
Massachusetts Bay Transportation Authority, Sales Tax Rev., “A”, 5%, 7/01/2024		2,590,000	2,617,485
Massachusetts Bay Transportation Authority, Sales Tax Rev., “A-1”, 5.25%, 7/01/2029		1,850,000	2,137,280
Massachusetts School Building Authority, Senior Dedicated Sales Tax Rev., “A”, 5%, 2/15/2044		4,000,000	4,307,493
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-1”, 4.55%, 7/01/2040		73,000	73,354
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-1”, 4.75%, 7/01/2053		239,000	236,527
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-1”, 5%, 7/01/2058		3,806,000	3,819,281
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.329%, 7/01/2040		597,000	592,650
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.329%, 7/01/2040		256,000	254,135
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.536%, 7/01/2053		5,000	4,780
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.784%, 7/01/2058		2,179,000	2,147,818
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2024		4,000	3,921
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2027		117,000	101,836
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2029		22,000	17,593
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2031		1,059,000	775,056
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2033		1,011,000	673,391
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2046		475,000	148,924
Wisconsin Public Finance Authority Limited Obligation Grant Rev. (American Dream at Meadowlands Project), “A”, 6.25%, 8/01/2027 (a)(d)(n)		585,000	456,300
Wisconsin Public Finance Authority Limited Obligation Grant Rev., Taxable (American Dream at Meadowlands Project), ”A“, 5.625%, 8/01/2024 (a)(d)(n)		360,000	280,800
			$18,941,385
Secondary Schools – 2.1%
Collegiate Charter School of Lowell, MA, Rev., 5%, 6/15/2054	$	1,000,000	$926,482
District of Columbia Rev. (Rocketship D.C.), “A”, 5%, 6/01/2056 (n)		290,000	251,347
Lowell, MA, Collegiate Charter School Rev., 5%, 6/15/2039		1,000,000	984,123

3

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Secondary Schools – continued
Massachusetts Development Finance Agency Rev. (Dexter Southfield), 5%, 5/01/2030	$	500,000	$511,603
Massachusetts Development Finance Agency Rev. (Dexter Southfield), 5%, 5/01/2031		1,015,000	1,038,386
Massachusetts Development Finance Agency Rev. (Foxborough Regional Charter School), “B”, 5%, 7/01/2037		1,000,000	1,015,671
Massachusetts Development Finance Agency Rev. (Roxbury Latin School), “A”, 3.5%, 7/01/2044		265,000	243,039
Massachusetts Development Finance Agency Rev. (Sabis International Charter School Issue), 5%, 4/15/2033		2,000,000	2,017,076
			$6,987,727
Single Family Housing - State – 3.8%
Connecticut Housing Finance Authority Rev. (Housing Mortgage Finance Program), “C-1”, 4%, 11/15/2047	$	490,000	$488,581
Massachusetts Housing Finance Agency, Single Family Housing Rev., “206”, 3.3%, 6/01/2034		365,000	358,528
Massachusetts Housing Finance Agency, Single Family Housing Rev., “206”, 3.45%, 12/01/2036		485,000	474,143
Massachusetts Housing Finance Agency, Single Family Housing Rev., “215”, GNMA, 4%, 12/01/2050		2,145,000	2,151,147
Massachusetts Housing Finance Agency, Single Family Housing Rev., “220”, GNMA, 1.35%, 12/01/2029		400,000	344,283
Massachusetts Housing Finance Agency, Single Family Housing Rev., “222”, GNMA, 3%, 6/01/2051		880,000	850,714
Massachusetts Housing Finance Agency, Single Family Housing Rev., “225”, 5.5%, 12/01/2052		3,925,000	4,183,728
Massachusetts Housing Finance Agency, Single Family Housing Rev., “230”, 4.3%, 6/01/2025		475,000	480,463
Massachusetts Housing Finance Agency, Single Family Housing Rev., “230”, 4.35%, 12/01/2025		525,000	534,053
Massachusetts Housing Finance Agency, Single Family Housing Rev., “230”, 4.45%, 6/01/2026		315,000	322,660
Massachusetts Housing Finance Agency, Single Family Housing Rev., “214”, GNMA, 2.95%, 12/01/2044		1,865,000	1,544,797
Massachusetts Housing Finance Agency, Single Family Housing Rev., Taxable, “231”, 4.7%, 12/01/2033		500,000	548,699
Massachusetts Housing Finance Agency, Single Family Housing Rev., Taxable, “231”, 4.75%, 12/01/2034		560,000	615,976
			$12,897,772
Student Loan Revenue – 6.2%
Massachusetts Educational Financing Authority, Education Loan Rev., “B”, 5%, 7/01/2029	$	1,400,000	$1,504,775
Massachusetts Educational Financing Authority, Education Loan Rev., “B”, 5%, 7/01/2030		1,300,000	1,414,817
Massachusetts Educational Financing Authority, Education Loan Rev., “B”, 2%, 7/01/2037		2,615,000	2,295,137
Massachusetts Educational Financing Authority, Education Loan Rev., “C”, 4.125%, 7/01/2046		2,250,000	2,030,131
Massachusetts Educational Financing Authority, Education Loan Rev., “C”, 3.75%, 7/01/2047		4,000,000	3,372,305
Massachusetts Educational Financing Authority, Education Loan Rev., “J”, 3.5%, 7/01/2033		635,000	613,419
Massachusetts Educational Financing Authority, Education Loan Rev., Issue L, “B”, 4.25%, 7/01/2044		3,000,000	3,013,512
Massachusetts Educational Financing Authority, Education Loan Rev., Issue M, “B”, 5%, 7/01/2031		1,000,000	1,097,943
Massachusetts Educational Financing Authority, Education Loan Subordinate Rev., “C”, 3%, 7/01/2051		2,000,000	1,409,154
Massachusetts Educational Financing Authority, Education Loan Subordinate Rev., “C”, 4.125%, 7/01/2052		3,000,000	2,601,279
Minnesota Office of Higher Education Supplemental Student Loan Program Rev., 2.65%, 11/01/2038		180,000	161,615
New Jersey Higher Education Student Assistance Authority, Senior Student Loan Rev., “B”, 4%, 12/01/2041		1,710,000	1,688,643
			$21,202,730
Tax - Other – 1.0%
Chicago, IL, Board of Education, Dedicated Capital Improvement Tax Bond, 5.75%, 4/01/2035	$	1,670,000	$1,757,053
Chicago, IL, Board of Education, Dedicated Capital Improvement Tax Bond, 5%, 4/01/2045		255,000	266,107
Chicago, IL, Board of Education, Dedicated Capital Improvement Tax Bond, 5.75%, 4/01/2048		710,000	776,461
Guam Government Limited Obligation Rev., “A”, 5%, 12/01/2036		120,000	122,926
Guam Government Limited Obligation Rev., “A”, 5%, 12/01/2046		370,000	368,837
Wisconsin Public Finance Authority Limited Obligation PILOT Rev. (American Dream at Meadowlands Project), 7%, 12/01/2050		225,000	209,602
			$3,500,986
Tax Assessment – 0.0%
Brunswick, MD, Special Obligation Refunding (Brunswick Crossing Special Taxing District), 4%, 7/01/2029	$	25,000	$24,673
Brunswick, MD, Special Obligation Refunding (Brunswick Crossing Special Taxing District), 5%, 7/01/2036		32,000	32,566
			$57,239
Tobacco – 0.9%
Buckeye, OH, Tobacco Settlement Financing Authority Senior Asset-Backed Refunding, 2020A-2, “1”, 4%, 6/01/2048	$	1,290,000	$1,191,393
Buckeye, OH, Tobacco Settlement Financing Authority Senior Asset-Backed Refunding, 2020B-2, “2”, 5%, 6/01/2055		800,000	751,804
Golden State, CA, Tobacco Securitization Corp., Tobacco Settlement Rev., Taxable, “B-1”, 3.85%, 6/01/2050		1,320,000	1,220,983
			$3,164,180

4

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Toll Roads – 0.3%
Massachusetts Department of Transportation, Metropolitan Highway System Refunding Rev., Subordinated Contract Assistance, 5%, 1/01/2037	$	1,000,000	$1,101,325
Transportation - Special Tax – 2.8%
Commonwealth of Massachusetts Transportation Fund Rev. (Rail Enhancement & Accelerated Bridge Programs), “A”, 5%, 6/01/2036	$	2,850,000	$2,988,154
Commonwealth of Massachusetts Transportation Fund Rev. (Rail Enhancement & Accelerated Bridge Programs), “A”, 5%, 6/01/2042		3,000,000	3,155,817
Commonwealth of Massachusetts Transportation Fund Rev. (Rail Enhancement Program), “B”, 5%, 6/01/2049		3,000,000	3,333,458
			$9,477,429
Universities - Colleges – 19.8%
Connecticut Health & Educational Facilities Authority Rev. (Connecticut College Issue), “M”, 3%, 7/01/2047	$	2,830,000	$2,138,246
Massachusetts Development Finance Agency Refunding Rev. (Brandeis University), “S-1”, 5%, 10/01/2038		3,015,000	3,283,236
Massachusetts Development Finance Agency Refunding Rev. (Brandeis University), “S-1”, 5%, 10/01/2040		2,665,000	2,885,320
Massachusetts Development Finance Agency Refunding Rev. (Olin College) “F”, 5%, 11/01/2040		850,000	956,228
Massachusetts Development Finance Agency Refunding Rev. (Olin College) “F”, 4%, 11/01/2041		1,800,000	1,847,399
Massachusetts Development Finance Agency Refunding Rev. (Olin College) “F”, 5%, 11/01/2042		950,000	1,060,598
Massachusetts Development Finance Agency Refunding Rev. (Olin College) “F”, 4.125%, 11/01/2043		1,250,000	1,284,853
Massachusetts Development Finance Agency Refunding Rev. (Suffolk University), 5%, 7/01/2035		970,000	1,015,071
Massachusetts Development Finance Agency Refunding Rev. (Suffolk University), 5%, 7/01/2036		850,000	872,738
Massachusetts Development Finance Agency Refunding Rev. (Suffolk University), 5%, 7/01/2037		625,000	646,311
Massachusetts Development Finance Agency Refunding Rev. (Suffolk University), 5%, 7/01/2038		340,000	348,904
Massachusetts Development Finance Agency Refunding Rev. (Suffolk University), 4%, 7/01/2039		3,055,000	2,839,341
Massachusetts Development Finance Agency Rev. (Bentley University), 5%, 7/01/2040		1,500,000	1,547,025
Massachusetts Development Finance Agency Rev. (Brandeis University), “R”, 5%, 10/01/2038		835,000	900,041
Massachusetts Development Finance Agency Rev. (Emerson College), 5%, 1/01/2043		725,000	737,868
Massachusetts Development Finance Agency Rev. (Emerson College), 5%, 1/01/2048		2,845,000	2,872,123
Massachusetts Development Finance Agency Rev. (Emerson College), “A”, 5.25%, 1/01/2042		2,000,000	2,043,586
Massachusetts Development Finance Agency Rev. (Emmanuel College), “A”, 5%, 10/01/2043		2,000,000	2,017,217
Massachusetts Development Finance Agency Rev. (Emmanuel College), “A”, 4%, 10/01/2046		1,375,000	1,204,132
Massachusetts Development Finance Agency Rev. (Lasell University), 4%, 7/01/2045		250,000	206,916
Massachusetts Development Finance Agency Rev. (Merrimack College), 5%, 7/01/2047		1,000,000	1,008,862
Massachusetts Development Finance Agency Rev. (Merrimack College), 5%, 7/01/2052		2,300,000	2,340,527
Massachusetts Development Finance Agency Rev. (Merrimack College), “B”, 4%, 7/01/2042		475,000	449,724
Massachusetts Development Finance Agency Rev. (Merrimack College), “B”, 4%, 7/01/2050		1,825,000	1,625,889
Massachusetts Development Finance Agency Rev. (Northeastern University), 5%, 10/01/2044		2,000,000	2,246,809
Massachusetts Development Finance Agency Rev. (Simmons University), “H”, SYNCORA, 5.25%, 10/01/2026		1,420,000	1,462,171
Massachusetts Development Finance Agency Rev. (Simmons University), “L”, 5%, 10/01/2035		2,000,000	2,093,264
Massachusetts Development Finance Agency Rev. (Simmons University), “M”, 5%, 10/01/2045		725,000	731,602
Massachusetts Development Finance Agency Rev. (Springfield College), “A”, 4%, 6/01/2056		3,000,000	2,453,069
Massachusetts Development Finance Agency Rev. (Suffolk University), 4%, 7/01/2046		1,000,000	873,282
Massachusetts Development Finance Agency Rev. (Suffolk University), 4%, 7/01/2051		1,385,000	1,164,544
Massachusetts Development Finance Agency Rev. (Wentworth Institute of Technology), 5%, 10/01/2046		2,000,000	2,011,407
Massachusetts Development Finance Agency Rev. (Western New England University), 5%, 9/01/2031		1,110,000	1,126,086
Massachusetts Development Finance Agency Rev. (Western New England University), AGM, 5%, 9/01/2038		2,550,000	2,732,307
Massachusetts Development Finance Agency Rev. (Worcester Polytechnic Institute), 5%, 9/01/2039		950,000	1,035,853
Massachusetts Development Finance Agency Rev. (Worcester Polytechnic Institute), 5%, 9/01/2047		1,395,000	1,454,340
Massachusetts Health & Educational Facilities Authority Rev. (Boston College), 5.5%, 6/01/2027		1,735,000	1,908,595
Massachusetts Health & Educational Facilities Authority Rev. (Massachusetts Institute of Technology), “I-1”, 5.2%, 1/01/2028		1,000,000	1,118,211
Massachusetts Health & Educational Facilities Authority Rev. (University of Massachusetts), “A”, 2.45%, 11/01/2030 (Put Date 4/01/2026)		3,500,000	3,459,257
Massachusetts Health & Educational Facilities Authority Rev. (Williams College), “I”, 0.7%, 7/01/2033 (Put Date 7/01/2025)		2,400,000	2,276,893
Puerto Rico Industrial, Tourist, Educational, Medical & Environmental Control Facilities Financing Authority, Educational Facilities Rev. (University Plaza Project), NPFG, 5%, 7/01/2033		265,000	259,243
Puerto Rico Industrial, Tourist, Educational, Medical & Environmental Control Facilities Financing Authority, Higher Education Rev. (University of Sacred Heart), 4.375%, 10/01/2031		75,000	75,060
Puerto Rico Industrial, Tourist, Educational, Medical & Environmental Control Facilities Financing Authority, Higher Education Rev. (University of Sacred Heart), 5%, 10/01/2042		90,000	90,175

5

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Universities - Colleges – continued
Red River, TX, Education Finance Corp., Higher Education Rev. (Houston Baptist University Project), 5.5%, 10/01/2046	$	470,000	$471,700
University of Massachusetts Building Authority Project Senior Rev., “1”, 5%, 11/01/2040		2,500,000	2,553,401
			$67,729,424
Utilities - Municipal Owned – 0.6%
Guam Power Authority Rev., “A”, AGM, 5%, 10/01/2039	$	200,000	$201,913
Guam Power Authority Rev., “A”, AGM, 5%, 10/01/2044		235,000	236,552
Puerto Rico Electric Power Authority Refunding Rev., “DDD”, 5%, 7/01/2020 (a)(d)		35,000	9,100
Puerto Rico Electric Power Authority Refunding Rev., “DDD”, 5%, 7/01/2021 (a)(d)		315,000	81,900
Puerto Rico Electric Power Authority Refunding Rev., “DDD”, 5%, 7/01/2022 (a)(d)		510,000	132,600
Puerto Rico Electric Power Authority Refunding Rev., “VV”, NPFG, 5.25%, 7/01/2029		385,000	379,250
Puerto Rico Electric Power Authority Refunding Rev., “VV”, NPFG, 5.25%, 7/01/2034		35,000	34,501
Puerto Rico Electric Power Authority Rev., “A”, 5%, 7/01/2029 (a)(d)		800,000	208,000
Puerto Rico Electric Power Authority Rev., “A”, 5%, 7/01/2042 (a)(d)		125,000	32,500
Puerto Rico Electric Power Authority Rev., “AAA”, 5.25%, 7/01/2021 (a)(d)		65,000	16,900
Puerto Rico Electric Power Authority Rev., “AAA”, 5.25%, 7/01/2030 (a)(d)		30,000	7,800
Puerto Rico Electric Power Authority Rev., “CCC”, 5.25%, 7/01/2027 (a)(d)		300,000	78,000
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2021 (a)(d)		150,000	39,000
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2023 (a)(d)		135,000	35,100
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2027 (a)(d)		25,000	6,500
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2037 (a)(d)		415,000	107,900
Puerto Rico Electric Power Authority Rev., “WW”, 5.375%, 7/01/2022 (a)(d)		30,000	7,800
Puerto Rico Electric Power Authority Rev., “WW”, 5.25%, 7/01/2025 (a)(d)		65,000	16,900
Puerto Rico Electric Power Authority Rev., “ZZ”, 5%, 7/01/2018 (a)(d)		195,000	50,700
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2023 (a)(d)		220,000	57,200
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2024 (a)(d)		75,000	19,500
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2026 (a)(d)		230,000	59,800
Puerto Rico Electric Power Authority Rev., Taxable, “EEE”, 6.05%, 7/01/2032 (a)(d)		190,000	46,075
			$1,865,491
Utilities - Other – 4.1%
California Community Choice Financing Authority, Clean Energy Project Rev., “C”, 5.25%, 1/01/2054 (Put Date 10/01/2031)	$	2,250,000	$2,380,098
Patriots Energy Group Financing Agency, SC, Gas Supply Rev., “B-1”, 5.25%, 2/01/2054 (Put Date 3/01/2031)		1,200,000	1,306,777
Southeast Alabama Energy Authority Commodity Supply Rev. (Project No. 5), “A”, 5.25%, 1/01/2054 (Put Date 7/01/2029)		2,065,000	2,197,562
Southeast Alabama Energy, Cooperative District Energy Supply Rev., “A-1”, 5.5%, 11/01/2053 (Put Date 1/01/2031)		2,720,000	2,978,149
Tennergy Corp., TN, Gas Supply Rev., “A”, 5.5%, 10/01/2053 (Put Date 12/01/2030)		1,270,000	1,355,595
Tennessee Energy Acquisition Corp., Gas Project Rev., “A”, 5.25%, 9/01/2026		1,610,000	1,661,627
Tennessee Energy Acquisition Corp., Gas Project Rev., “A-1”, 5%, 5/01/2053 (Put Date 5/01/2028)		2,020,000	2,108,780
			$13,988,588
Water & Sewer Utility Revenue – 1.9%
Guam Waterworks Authority Rev. (Water and Wastewater System), “A”, 5%, 1/01/2050	$	455,000	$468,299
Massachusetts Water Pollution Abatement Trust, 5.25%, 8/01/2027		1,280,000	1,410,708
Massachusetts Water Pollution Abatement Trust, 5.25%, 8/01/2033		2,000,000	2,510,871
Massachusetts Water Pollution Abatement Trust (MWRA Program), “A”, 5%, 8/01/2032		75,000	75,111
Massachusetts Water Resources Authority, General Rev., “B”, 5%, 8/01/2042		430,000	491,335
Massachusetts Water Resources Authority, General Rev., “B”, 5%, 8/01/2043		750,000	853,993
Massachusetts Water Resources Authority, General Rev., “B”, AGM, 5.25%, 8/01/2029		595,000	690,720
			$6,501,037
Total Municipal Bonds			$329,159,764
Bonds – 0.3%
Consumer Services – 0.3%
Toll Road Investors Partnership II LP, Capital Appreciation, NPFG, 0%, 2/15/2025 (n)	$	581,000	$537,610
Toll Road Investors Partnership II LP, Capital Appreciation, NPFG, 0%, 2/15/2043 (n)		1,134,593	360,905
Total Bonds			$898,515

6

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Contingent Value Instruments – 0.1%
General Obligations - General Purpose – 0.1%
Commonwealth of Puerto Rico, General Obligation Contingent Value Instrument, 11/01/2043	$	636,896	$347,108
Investment Companies (h) – 2.1%
Money Market Funds – 2.1%
MFS Institutional Money Market Portfolio, 5.42% (v)		7,242,735	$7,244,184
Other Assets, Less Liabilities – 1.3%			4,565,978
Net Assets – 100.0%			$342,215,549

(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 $7,244,184 and $330,405,387, 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 $8,124,602, representing 2.4% 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
FHA	Federal Housing Administration
GNMA	Government National Mortgage Assn.
NPFG	National Public Finance Guarantee Corp.
SYNCORA	Syncora Guarantee Inc.
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.

7

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	$—	$329,506,872	$—	$329,506,872
U.S. Corporate Bonds	—	898,515	—	898,515
Mutual Funds	7,244,184	—	—	7,244,184
Total	$7,244,184	$330,405,387	$—	$337,649,571

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	$8,411,492	$84,339,859	$85,504,682	$(2,284)	$(201)	$7,244,184

8

Supplemental Information (unaudited) – continued

Affiliated Issuers	Dividend Income	Capital Gain Distributions
MFS Institutional Money Market Portfolio	$209,262	$—

(3) Jurisdiction Weightings

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

Massachusetts	79.2%
Puerto Rico	3.8%
California	3.7%
Illinois	2.0%
Alabama	1.6%
Tennessee	1.5%
Texas	1.0%
New York	0.9%
Connecticut	0.8%
Ohio	0.6%
Guam	0.5%
New Jersey	0.5%
Pennsylvania	0.5%
South Carolina	0.4%
New Hampshire	0.3%
Virginia	0.3%
Wisconsin	0.3%
Colorado	0.1%
Washington DC	0.1%
Maryland (o)	0.0%
Minnesota (o)	0.0%
U.S. Virgin Islands (o)	0.0%

(o) Less than 0.1%.

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

9