MFS Municipal Income R6 (MPMNX) NPORT-P MFS Pennsylvania Municipal Bond Fund (Jun 2024 report)

Quarterly Report

June 30, 2024

MFS^®Pennsylvania
Municipal Bond Fund

MPA-Q1

Portfolio of Investments

6/30/24 (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 – 100.4%
Airport Revenue – 3.5%
Allegheny County, PA, Airport Authority Rev. (Pittsburgh International Airport), “A”, AGM, 5.5%, 1/01/2048	$	1,000,000	$1,095,218
Allegheny County, PA, Airport Authority Rev. (Pittsburgh International Airport), “A”, AGM, 5.5%, 1/01/2053		1,000,000	1,086,377
New York Transportation Development Corp., Special Facilities Rev. (John F. Kennedy International Airport New Terminal One Project), AGM, 5.25%, 6/30/2060		755,000	790,472
Philadelphia, PA, Airport Refunding Rev., 5%, 7/01/2029		1,590,000	1,677,721
Philadelphia, PA, Airport Rev., “B”, 5%, 7/01/2034		750,000	771,130
Wayne County, MI, Airport Authority Rev. (Detroit Metropolitan Wayne County Airport), “B”, 5%, 12/01/2044		55,000	55,088
Wayne County, MI, Airport Authority Rev. (Detroit Metropolitan Wayne County Airport), “B”, BAM, 5%, 12/01/2039		65,000	65,200
Wayne County, MI, Airport Authority Rev. (Detroit Metropolitan Wayne County Airport), “C”, 5%, 12/01/2039		45,000	45,072
Wayne County, MI, Airport Authority Rev. (Detroit Metropolitan Wayne County Airport), “C”, 5%, 12/01/2044		80,000	80,052
			$5,666,330
General Obligations - General Purpose – 6.6%
Allegheny County, PA, Bethel Park School District General Obligation, 5.5%, 8/01/2048	$	1,000,000	$1,118,012
Berks County, PA, Reading General Obligation, BAM, 5%, 11/01/2030		1,000,000	1,065,676
Berks County, PA, Reading General Obligation, BAM, 5%, 11/01/2031		1,000,000	1,066,861
Bridgeview, IL, Stadium and Redevelopment Projects, Taxable, AAC, 5.14%, 12/01/2036		350,000	313,876
Bucks County, PA, Northampton Township, General Obligation, 4%, 5/15/2043		1,000,000	1,000,838
Chicago, IL, General Obligation, “A”, 5%, 1/01/2025		220,000	221,097
Chicago, IL, General Obligation, “A”, 5.5%, 1/01/2040		600,000	649,114
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, “A”, 5.625%, 7/01/2029		66,341	71,152
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, “A”, 5.75%, 7/01/2031		245,437	272,543
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, “A”, 4%, 7/01/2033		61,103	61,195
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, “A”, 4%, 7/01/2035		116,918	114,774
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, “A”, 4%, 7/01/2037		47,139	45,378
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, “A”, 4%, 7/01/2041		64,091	59,733
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, “A”, 4%, 7/01/2046		234,653	212,281
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Capital Appreciation, “A”, 0%, 7/01/2024		9,939	9,939
Commonwealth of Puerto Rico, General Obligation Restructured Bonds, Capital Appreciation, “A”, 0%, 7/01/2033		78,634	52,469
Lancaster, PA, General Obligation, BAM, 5%, 11/01/2034		1,890,000	2,099,285
Penn Hills, PA, General Obligation, Capital Appreciation, “D”, 0%, 12/01/2032		595,000	415,398
Philadelphia, PA, Energy Authority City Service Agreement Rev. (Philadelphia Street Lighting Project), “A”, 5%, 11/01/2042		1,000,000	1,078,750
State of Illinois, General Obligation, 5.5%, 5/01/2039		125,000	136,834
State of Illinois, General Obligation, 5.75%, 5/01/2045		115,000	124,902
State of Illinois, General Obligation, “B”, 5.5%, 5/01/2047		130,000	141,460
Texas Cedar Port Navigation & Improvement District, Unlimited Tax, 4.5%, 9/01/2048		165,000	166,292
Texas Cedar Port Navigation & Improvement District, Unlimited Tax, 4.5%, 9/01/2052		65,000	65,168
			$10,563,027
General Obligations - Schools – 11.2%
Beaver County, PA, Aliquippa School District General Obligation, BAM, 4%, 12/01/2041	$	1,000,000	$1,002,800
Berks County, PA, Muhlenberg School District General Obligation, 5%, 5/15/2054 (w)		1,000,000	1,052,380
Berks County, PA, Reading School District, AGM, 5%, 3/01/2038		1,000,000	1,026,037
Bucks County, PA, Pennsbury School District General Obligation, 5%, 8/01/2043 (w)		560,000	603,952
Bucks County, PA, Pennsbury School District General Obligation, 5%, 8/01/2044 (w)		1,000,000	1,075,920
Coatesville, PA, Area School District, General Obligation, AGM, 5%, 8/01/2024		970,000	970,890
Conneaut, PA, School District, Capital Appreciation, “B”, AGM, 0%, 11/01/2031		1,150,000	854,422
Delaware County, PA, Interboro School District General Obligation, AGM, 5.5%, 8/15/2063 (w)		1,500,000	1,630,886
Erie, PA, City School District General Obligation, “A”, AGM, 4%, 4/01/2033		1,050,000	1,065,359
Luzerne County, PA, Wilkes-Barre Area School District, General Obligation, BAM, 4%, 4/15/2054		765,000	739,219
Luzerne County, PA, Wilkes-Barre Area School District, General Obligation, BAM, 5%, 4/15/2059		1,500,000	1,539,112
Montgomery County, PA, Springfield Township School District, General Obligation, 4%, 11/15/2037		1,500,000	1,504,747
Philadelphia, PA, School District General Obligation, “F”, 5%, 9/01/2038 (Prerefunded 9/01/2026)		5,000	5,186
Philadelphia, PA, School District General Obligation, “F”, 5%, 9/01/2038		1,495,000	1,510,753
Philadelphia, PA, School District, “A”, 5%, 9/01/2044		1,500,000	1,558,821
Scranton, PA, School District, “E”, BAM, 5%, 12/01/2034		1,000,000	1,049,761

1

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
General Obligations - Schools – continued
Upper St. Clair Township, PA, School District General Obligation, “B”, 3.625%, 10/01/2039	$	1,000,000	$936,881
			$18,127,126
Healthcare Revenue - Hospitals – 14.9%
Allegheny County, PA, Mt. Lebanon Hospital Authority Rev. (St. Clair Memorial Hospital), 5%, 7/01/2038	$	1,000,000	$1,039,031
Berks County, PA, Industrial Development Authority Health System Rev. (Tower Health Project), 4%, 11/01/2038		500,000	315,000
Berks County, PA, Municipal Authority Rev. (Reading Hospital & Medical Center), “A”, 5%, 11/01/2040		1,600,000	1,008,000
Bucks County, PA, Industrial Development Authority, Hospital Rev. (St. Luke's University Health Network Project), 4%, 8/15/2044		1,000,000	931,463
Bucks County, PA, St. Mary Hospital Authority Refunding Rev. (Trinity Health Credit Group), 5%, 12/01/2048 (Prerefunded 12/01/2028)		665,000	719,155
Bucks County, PA, St. Mary Hospital Authority Refunding Rev. (Trinity Health Credit Group), 5%, 12/01/2048		335,000	343,345
Centre County, PA, Hospital Authority Rev. (Mount Nittany Medical Center), 5%, 11/15/2041 (Prerefunded 11/15/2025)		850,000	868,380
Chester County, PA, Health & Education Facilities Authority Health System Rev. (Main Line Health System), “A”, 5%, 10/01/2052		1,750,000	1,785,103
Doylestown, PA, Hospital Authority Rev., “A”, 5%, 7/01/2049 (Prerefunded 7/01/2029)		100,000	107,874
Doylestown, PA, Hospital Authority Rev., “A”, 5%, 7/01/2049		900,000	873,751
DuBois, PA, Hospital Authority Rev. (Penn Highlands Healthcare), 5%, 7/15/2039		500,000	509,053
DuBois, PA, Hospital Authority Rev. (Penn Highlands Healthcare), 5%, 7/15/2040		1,000,000	1,014,421
DuBois, PA, Hospital Authority Rev. (Penn Highlands Healthcare), 5%, 7/15/2043		1,000,000	1,005,256
Fulton County, PA, Industrial Development Authority Hospital Rev. (Medical Center Project), 5%, 7/01/2040		500,000	421,644
Harris County, TX, Cultural Education Facilities Finance Corp., Hospital Rev. (Memorial Hermann Health System), “A”, 4.125%, 7/01/2052		900,000	858,936
Lancaster County, PA, Hospital Authority Rev. (University of Pennsylvania Health System), “A”, 5%, 8/15/2036		1,000,000	1,028,653
Lehigh County, PA, Hospital Authority Rev. (Lehigh Valley Health Network), “A”, 4%, 7/01/2039		1,000,000	993,288
Montgomery County, PA, Higher Education & Health Authority Rev. (Thomas Jefferson University), “B”, 4%, 5/01/2042		2,000,000	1,950,551
Montour County, PA, Geisinger Authority Health System Rev., “A”, 4%, 4/01/2039		1,000,000	985,250
Montour County, PA, Geisinger Authority Health System Rev., “A-1”, 5%, 2/15/2045		1,000,000	1,016,032
Northampton County, PA, General Purpose Authority Hospital Rev. (St. Luke's Hospital), “A”, 5%, 8/15/2048		500,000	510,041
Pennsylvania Economic Development Financing Authority, UPMC Rev., “A”, 4%, 5/15/2053		1,000,000	927,767
Philadelphia, PA, Authority for Industrial Development Rev. (Thomas Jefferson University), “A”, 5%, 9/01/2036		1,000,000	1,025,366
Philadelphia, PA, Authority for Industrial Development Rev. (Thomas Jefferson University), “A”, 5%, 9/01/2042		1,000,000	1,013,024
Philadelphia, PA, Hospitals and Higher Education Facilities Authority Rev. (Temple University Health System Obligated Group), “A”, 5%, 7/01/2034		500,000	506,180
Southcentral, PA, General Authority Rev. (WellSpan Health Obligated Group), 4%, 6/01/2044		1,000,000	957,774
Westmoreland County, PA, Industrial Development Authority, Health System Rev. (Excela Health Project), “A”, 4%, 7/01/2037		1,400,000	1,279,454
			$23,993,792
Healthcare Revenue - Long Term Care – 4.1%
Chester County, PA, Health & Education Facilities Authority Rev. (Simpson Senior Services Project), “A”, 5.25%, 12/01/2045	$	500,000	$337,645
Cumberland County, PA, Municipal Authority Rev. (Diakon Lutheran Social Ministries), “A”, 5%, 1/01/2039		140,000	142,652
Cumberland County, PA, Municipal Authority Rev. (Diakon Lutheran Social Ministries), “A”, ETM, 5%, 1/01/2039 (Prerefunded 1/01/2029)		95,000	101,249
Cumberland County, PA, Municipal Authority Rev. (Diakon Lutheran Social Ministries), “A”, ETM, 5%, 1/01/2039 (Prerefunded 1/01/2029)		765,000	815,317
East Hempfield Township, PA, Industrial Development Authority Rev. (Willow Valley Communities Project), 5%, 12/01/2039		750,000	758,866
Lancaster County, PA, Hospital Authority Health Center Rev. (Landis Homes Retirement Community Project), “A”, 5%, 7/01/2045		500,000	475,060
Lancaster County, PA, Hospital Authority Health Center Rev. (Masonic Villages Project), 5%, 11/01/2035		500,000	504,605
Lancaster County, PA, Hospital Authority Health Center Rev. (Masonic Villages Project), 5%, 11/01/2036		260,000	268,819
Lancaster County, PA, Hospital Authority Health Center Rev. (Masonic Villages Project), 5%, 11/01/2037		250,000	258,181
Lancaster County, PA, Hospital Authority Rev. (Brethren Village Project), 5.125%, 7/01/2037		500,000	489,558
Lancaster County, PA, Hospital Authority Rev. (Saint Anne's Retirement Community, Inc. Project), 5%, 3/01/2040		500,000	453,409
Lancaster County, PA, Hospital Authority Rev. (Saint Anne's Retirement Community, Inc. Project), 5%, 3/01/2045		500,000	433,199
Montgomery County, PA, Industrial Development Authority Rev. (Whitemarsh Continuing Care Retirement Community Project), 5.375%, 1/01/2050		400,000	373,984
Pennsylvania Economic Development Financing Authority Rev. (Presbyterian Senior Living Project), “B-1”, 5.25%, 7/01/2049		750,000	784,365
Philadelphia, PA, Authority for Industrial Development, Senior Living Facilities Rev. (Wesley Enhanced Living Obligated Group), “A”, 5%, 7/01/2049		500,000	428,770
			$6,625,679

2

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Industrial Revenue - Environmental Services – 1.0%
Blythe, PA, Solid Waste Authority Rev., 7.75%, 12/01/2037 (Prerefunded 12/01/2027)	$	225,000	$248,834
California Municipal Finance Authority, Solid Waste Disposal Rev. (Waste Management, Inc. Project), “A”, 4.25%, 12/01/2044 (Put Date 12/02/2024)		290,000	290,103
Pennsylvania Economic Development Financing Authority, Solid Waste Disposal Rev. (Waste Management, Inc. Project), “A-2”, 4.6%, 10/01/2046 (Put Date 10/01/2026)		1,000,000	1,014,341
			$1,553,278
Industrial Revenue - Other – 0.7%
Pennsylvania Economic Development Financing Authority, Solid Waste Disposal Rev. (Procter & Gamble), 5.375%, 3/01/2031	$	1,000,000	$1,103,700
Miscellaneous Revenue - Other – 1.8%
Director of the State of Nevada, Department of Business & Industry Rev. (Brightline West Passenger Rail Project), “A”, 4%, 1/01/2050 (Put Date 1/30/2025)	$	100,000	$100,024
Matching Fund Special Purpose Securitization Corp., “A”, 5%, 10/01/2026		65,000	66,423
New York Liberty Development Corp., Liberty Rev. (3 World Trade Center Project), “1”, 5%, 11/15/2044 (n)		395,000	395,375
Pennsylvania Economic Development Authority Rev. (Capitol Region Parking System), AGM, 4%, 1/01/2041		1,300,000	1,278,551
Pennsylvania Economic Development Financing Authority, Private Activity Rev. (Pennsylvania Rapid Bridge Replacement Project), 5%, 12/31/2034		970,000	982,128
			$2,822,501
Multi-Family Housing Revenue – 2.0%
National Finance Authority, NH, Municipal Certificates, “1-A”, 4.375%, 9/20/2036	$	457,183	$454,310
New Mexico Mortgage Finance Authority, Multi-Family Housing Rev. (Mountain View II & III Apartments Project), HUD Section 8, 5%, 2/01/2042 (Put Date 9/01/2025)		225,000	226,631
New Mexico Mortgage Finance Authority, Multi-Family Housing Rev. (Santa Fe Apartment & Sangre de Cristo Project), HUD Section 8, 5%, 2/01/2042 (Put Date 6/01/2025)		355,000	355,691
Pennsylvania Housing Finance Agency, Special Limited Obligation, Multi-Family Housing Development Rev. (Country Commons Apartments), FNMA, 3.6%, 8/01/2035		927,633	868,622
Philadelphia, PA, Authority for Industrial Development, Multi-Family Housing Rev. (University Square Apartment Project-Section 8), “I”, 5%, 12/01/2058		1,250,000	1,244,364
			$3,149,618
Port Revenue – 0.1%
New York Liberty Development Corp., Liberty Refunding Rev. (1 World Trade Center Project), 2.75%, 2/15/2044	$	300,000	$224,764
Sales & Excise Tax Revenue – 2.6%
Guam Government Business Privilege Tax Refunding, “F”, 5%, 1/01/2031	$	10,000	$10,663
Guam Government Business Privilege Tax Refunding, “F”, 4%, 1/01/2042		120,000	115,414
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-1”, 4.55%, 7/01/2040		35,000	35,131
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-1”, 4.75%, 7/01/2053		124,000	122,194
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-1”, 5%, 7/01/2058		1,979,000	1,971,296
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.329%, 7/01/2040		243,000	239,742
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.329%, 7/01/2040		116,000	114,445
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.536%, 7/01/2053		1,000	952
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “2019A-2”, 4.784%, 7/01/2058		364,000	358,229
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2024		2,000	2,000
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2029		9,000	7,427
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2031		524,000	397,757
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2033		509,000	353,875
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “2019A-1”, 0%, 7/01/2046		227,000	73,000
Wisconsin Public Finance Authority Limited Obligation Grant Rev. (American Dream at Meadowlands Project), “A”, 6.25%, 8/01/2027 (a)(d)(n)		195,000	152,100
Wisconsin Public Finance Authority Limited Obligation Grant Rev., Taxable (American Dream at Meadowlands Project), ”A“, 5.625%, 8/01/2024 (a)(d)(n)		205,000	159,900
			$4,114,125

3

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Secondary Schools – 2.4%
Bucks County, PA, Industrial Development Authority Rev. (School Lane Charter School Project), “A”, 5.125%, 3/15/2046	$	500,000	$500,076
Chester County, PA, Industrial Development Authority Educational Facilities Rev. (Avon Grove Charter School), “A”, 5%, 12/15/2047		500,000	497,150
Montgomery County, PA, Industrial Development Authority Rev. (Germantown Academy Project), “A”, 4%, 10/01/2046		625,000	541,942
Philadelphia, PA, Authority for Industrial Development Charter School Rev. (Tacony Academy School Project), 5.5%, 6/15/2043 (n)		500,000	521,156
Philadelphia, PA, Authority for Industrial Development Rev. (A String Theory Charter School Project), 5%, 6/15/2040 (n)		900,000	915,794
Philadelphia, PA, Authority for Industrial Development Rev. (MaST Charter School Project), “B”, 6%, 8/01/2051		450,000	459,937
Philadelphia, PA, Authority for Industrial Development Rev. (MaST Community Charter School II Project), 5%, 8/01/2050		500,000	505,038
			$3,941,093
Single Family Housing - State – 8.3%
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., 4.6%, 10/01/2049 (n)	$	1,000,000	$994,223
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., 6%, 10/01/2054 (n)		1,500,000	1,621,268
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., “128A”, 3.65%, 10/01/2032		1,000,000	938,357
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., “135A”, 3%, 10/01/2051		1,445,000	1,410,938
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., “141A”, 4.6%, 10/01/2043		1,000,000	1,009,203
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., “141A”, 4.7%, 10/01/2046		1,000,000	1,005,002
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., “145A”, 4.75%, 10/01/2049		1,000,000	1,004,295
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., “134B”, 5%, 4/01/2025		500,000	502,532
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., “134B”, 5%, 10/01/2025		300,000	302,215
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., “134B”, 5%, 10/01/2026		1,545,000	1,569,441
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., “141A”, 5.75%, 10/01/2053		1,450,000	1,530,251
Pennsylvania Housing Finance Agency, Single Family Mortgage Rev., “142A”, 5.5%, 10/01/2053		1,485,000	1,559,400
			$13,447,125
State & Local Agencies – 3.9%
Chester County, PA, Health & Education Facilities Authority Rev. (Chester County Intermediate Unit Project), BAM, 5%, 4/01/2042	$	1,375,000	$1,464,661
Chester County, PA, Health & Education Facilities Authority Rev. (Chester County Intermediate Unit Project), BAM, 5%, 4/01/2043		500,000	531,714
Chester County, PA, Health & Education Facilities Authority Rev. (Chester County Intermediate Unit Project), BAM, 5%, 4/01/2044		650,000	688,878
Pennsylvania Public School Building Authority, School Lease Rev. (School District of Philadelphia Project), “A”, AGM, 5%, 6/01/2033		1,255,000	1,289,451
Philadelphia, PA, Authority for Industrial Development Rev. (Rebuild Project), 5%, 5/01/2037		250,000	263,792
Philadelphia, PA, Authority for Industrial Development Rev. (Rebuild Project), 5%, 5/01/2038		1,000,000	1,053,152
Philadelphia, PA, Redevelopment Authority City Agreement Rev., “A”, 5%, 4/15/2028		1,000,000	1,011,034
			$6,302,682
Student Loan Revenue – 4.1%
New Jersey Higher Education Student Assistance Authority, Senior Student Loan Rev., “B”, 4%, 12/01/2041	$	820,000	$786,020
Pennsylvania Higher Educational Assistance Agency, Education Loan Rev., “1A”, 4.125%, 6/01/2045		750,000	718,845
Pennsylvania Higher Educational Assistance Agency, Education Loan Rev., “1C”, 5%, 6/01/2051		750,000	744,125
Pennsylvania Higher Educational Assistance Agency, Education Loan Rev., “A”, 5%, 6/01/2029		325,000	336,643
Pennsylvania Higher Educational Assistance Agency, Education Loan Rev., “A”, 5%, 6/01/2030		400,000	416,042
Pennsylvania Higher Educational Assistance Agency, Education Loan Rev., “A”, 2.625%, 6/01/2042		815,000	686,877
Pennsylvania Higher Educational Assistance Agency, Education Loan Rev., “A”, 4.5%, 6/01/2043		1,615,000	1,615,670
Pennsylvania Higher Educational Assistance Agency, Education Loan Rev., “A”, 4%, 6/01/2044		875,000	837,049
Pennsylvania Higher Educational Assistance Agency, Education Loan Rev., “B”, 5%, 6/01/2050		500,000	495,232
			$6,636,503
Tax - Other – 3.8%
Allentown, PA, Neighborhood Improvement Zone Development Authority Tax Refunding Rev., 5%, 5/01/2042	$	1,000,000	$1,030,351
Allentown, PA, Neighborhood Improvement Zone Development Authority Tax Rev. (City Center Project), 5.375%, 5/01/2042 (n)		300,000	299,598
Allentown, PA, Neighborhood Improvement Zone Development Authority Tax Rev. (City Center Refunding Project), 5%, 5/01/2042 (n)		500,000	501,457
Chicago, IL, Board of Education, Dedicated Capital Improvement Tax Bond, 5.75%, 4/01/2035		675,000	711,365
Chicago, IL, Board of Education, Dedicated Capital Improvement Tax Bond, 5%, 4/01/2045		110,000	116,878

4

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Tax - Other – continued
Chicago, IL, Board of Education, Dedicated Capital Improvement Tax Bond, 5.75%, 4/01/2048	$	285,000	$317,047
Guam Government Limited Obligation Rev., “A”, 5%, 12/01/2024		480,000	481,667
Guam Government Limited Obligation Rev., “A”, 5%, 12/01/2036		60,000	61,150
Guam Government Limited Obligation Rev., “A”, 5%, 12/01/2046		185,000	185,510
Lancaster County, PA, Convention Center Authority Hotel Room Rental Tax Rev., “B”, 4%, 5/01/2049		500,000	466,525
New York, NY, Transitional Finance Authority Rev., “C-1”, 4%, 5/01/2045		1,320,000	1,298,363
St. Clair County, AL, Board of Education, Special Tax School Warrants (15 Mill Moody Tax), “A”, BAM, 4.25%, 2/01/2052		500,000	500,238
Wisconsin Public Finance Authority Limited Obligation PILOT Rev. (American Dream at Meadowlands Project), 7%, 12/01/2050		105,000	104,615
			$6,074,764
Tax Assessment – 0.3%
Washington County, PA, Redevelopment Authority Refunding Rev. (Victory Centre Tax Increment Financing Project), 5%, 7/01/2035	$	500,000	$497,522
Tobacco – 0.7%
Buckeye, OH, Tobacco Settlement Financing Authority Senior Asset-Backed Refunding, 2020A-2, “1”, 4%, 6/01/2048	$	540,000	$497,704
Buckeye, OH, Tobacco Settlement Financing Authority Senior Asset-Backed Refunding, 2020B-2, “2”, 5%, 6/01/2055		300,000	276,558
Golden State, CA, Tobacco Securitization Corp., Tobacco Settlement Rev., Taxable, “B-1”, 3.85%, 6/01/2050		450,000	422,044
			$1,196,306
Toll Roads – 0.9%
Pennsylvania Turnpike Commission Subordinate Rev., “A”, AGM, 4%, 12/01/2049	$	1,500,000	$1,435,279
Transportation - Special Tax – 1.5%
New Jersey Transportation Trust Fund Authority, “A”, 5%, 12/15/2039	$	85,000	$90,055
New Jersey Transportation Trust Fund Authority, “CC”, 5.5%, 6/15/2050		90,000	99,212
Southeastern Pennsylvania Transportation Authority Rev. (Asset Improvement Program), 5.25%, 6/01/2047		2,000,000	2,190,883
			$2,380,150
Universities - Colleges – 13.5%
Allegheny County, PA, Higher Education Building Authority Rev. (Duquesne University), “A”, 5%, 3/01/2032 (Prerefunded 3/01/2025)	$	500,000	$504,981
Allegheny County, PA, Higher Education Building Authority Rev. (Duquesne University), “A”, 4%, 3/01/2041		1,000,000	989,913
Clemson University, SC, Athletic Facilities Rev., “A”, 3%, 5/01/2048		1,500,000	1,170,381
Commonwealth of Pennsylvania, State Public School Building Authority Lease Rev. (Montgomery County Community College), 5%, 5/01/2033 (Prerefunded 5/01/2025)		145,000	146,620
Commonwealth of Pennsylvania, State Public School Building Authority Lease Rev. (Montgomery County Community College), 5%, 5/01/2033		855,000	863,051
Erie, PA, Higher Education Building Authority Rev. (AICUP Financing Program-Gannon University Project), 4%, 5/01/2036		300,000	275,928
Erie, PA, Higher Education Building Authority Rev. (AICUP Financing Program-Gannon University Project), 4%, 5/01/2041		920,000	789,724
Indiana County, PA, Industrial Development Authority Refunding Rev. (Foundation for Indiana University of Pennsylvania Project), BAM, 4%, 5/01/2054		2,750,000	2,622,332
Lehigh County, PA, General Purpose Authority, College Rev. (Muhlenberg College Project), 5.25%, 2/01/2054		1,000,000	1,045,957
Montgomery County, PA, Higher Education & Health Authority Rev. (Thomas Jefferson University), “B”, AGM, 3.125%, 5/01/2053		95,000	72,521
Northampton County, PA, General Purpose Authority College Rev. (Lafayette College), 4%, 11/01/2038		1,000,000	1,001,205
Northeastern, PA, Hospital & Education Authority College Rev. (King's College Project), 5%, 5/01/2049		1,000,000	923,966
Pennsylvania Economic Development Authority Rev. (Villanova University Project), 5%, 8/01/2049		1,000,000	1,096,350
Pennsylvania Higher Educational Facilities Authority Rev. (Drexel University), “A”, AGM, 5%, 5/01/2046		1,750,000	1,829,869
Pennsylvania Higher Educational Facilities Authority Rev. (Duquesne University), “A”, 5%, 3/01/2039		750,000	781,632
Pennsylvania Higher Educational Facilities Authority Rev. (Widener University), “A”, 4%, 7/15/2051		1,250,000	993,134
Pennsylvania Public School Building Authority, College Rev. (Delaware County Community College Project), BAM, 5%, 10/01/2038		1,200,000	1,295,141
Pennsylvania State University, Tax-Exempt, “A”, 5.25%, 9/01/2052		3,000,000	3,293,249
Philadelphia, PA, Authority for Industrial Development University Rev. (Saint Joseph's University Project), 5.5%, 11/01/2060		1,000,000	1,067,626
University of Puerto Rico Rev., “P”, NPFG, 5%, 6/01/2025		25,000	25,026
Wilkes-Barre, PA, Finance Authority Rev. (University of Scranton), “A”, 5%, 11/01/2026		1,000,000	1,016,359
			$21,804,965

5

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Utilities - Municipal Owned – 0.9%
Guam Power Authority Rev., “A”, AGM, 5%, 10/01/2039	$	95,000	$95,223
Guam Power Authority Rev., “A”, AGM, 5%, 10/01/2044		105,000	105,149
Philadelphia, PA, Gas Works Rev., 5%, 8/01/2031		500,000	505,729
Puerto Rico Electric Power Authority Refunding Rev., “DDD”, 5%, 7/01/2020 (a)(d)		15,000	7,519
Puerto Rico Electric Power Authority Refunding Rev., “DDD”, 5%, 7/01/2021 (a)(d)		150,000	75,187
Puerto Rico Electric Power Authority Refunding Rev., “DDD”, 5%, 7/01/2022 (a)(d)		245,000	122,806
Puerto Rico Electric Power Authority Rev., “A”, 5%, 7/01/2029 (a)(d)		390,000	195,487
Puerto Rico Electric Power Authority Rev., “AAA”, 5.25%, 7/01/2021 (a)(d)		25,000	12,531
Puerto Rico Electric Power Authority Rev., “AAA”, 5.25%, 7/01/2030 (a)(d)		15,000	7,519
Puerto Rico Electric Power Authority Rev., “CCC”, 5.25%, 7/01/2027 (a)(d)		140,000	70,175
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2021 (a)(d)		65,000	32,581
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2027 (a)(d)		10,000	5,013
Puerto Rico Electric Power Authority Rev., “TT”, 5%, 7/01/2037 (a)(d)		200,000	100,250
Puerto Rico Electric Power Authority Rev., “VV”, NPFG, 5.25%, 7/01/2034		15,000	14,839
Puerto Rico Electric Power Authority Rev., “WW”, 5.375%, 7/01/2022 (a)(d)		10,000	5,013
Puerto Rico Electric Power Authority Rev., “WW”, 5.25%, 7/01/2025 (a)(d)		30,000	15,038
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2023 (a)(d)		105,000	52,631
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2024 (a)(d)		30,000	15,038
Puerto Rico Electric Power Authority Rev., “ZZ”, 5.25%, 7/01/2026 (a)(d)		95,000	47,619
Puerto Rico Electric Power Authority Rev., Taxable, “EEE”, 6.05%, 7/01/2032 (a)(d)		80,000	40,100
			$1,525,447
Utilities - Other – 3.2%
Black Belt Energy Gas District, AL, Gas Project Rev., “C-1”, 5.25%, 2/01/2053 (Put Date 6/01/2029)	$	935,000	$986,740
California Community Choice Financing Authority, Clean Energy Project Rev., “C”, 5.25%, 1/01/2054 (Put Date 10/01/2031)		925,000	974,830
Patriots Energy Group Financing Agency, SC, Gas Supply Rev., “B-1”, 5.25%, 2/01/2054 (Put Date 3/01/2031)		550,000	595,485
Public Authority for Colorado Energy Natural Gas Purchase Rev., 6.5%, 11/15/2038		280,000	343,135
Southeast Alabama Energy Authority Commodity Supply Rev. (Project No. 5), “A”, 5.25%, 1/01/2054 (Put Date 7/01/2029)		845,000	893,519
Tennergy Corp., TN, Gas Supply Rev., “A”, 5.5%, 10/01/2053 (Put Date 12/01/2030)		520,000	555,595
Tennessee Energy Acquisition Corp., Gas Project Rev., “A-1”, 5%, 5/01/2053 (Put Date 5/01/2028)		825,000	857,562
			$5,206,866
Water & Sewer Utility Revenue – 8.4%
Allegheny County, PA, Sanitation Authority Sewer Rev., 5%, 6/01/2053	$	1,000,000	$1,058,308
Allegheny County, PA, Sanitation Authority Sewer Rev., BAM, 5%, 12/01/2030		500,000	508,270
Bucks County, PA, Water & Sewer Authority, Sewer System Rev. “A”, AGM, 4.25%, 12/01/2047		2,000,000	1,973,229
Canonsburg-Houston, PA, Joint Authority Sewer Rev., “A”, 5%, 12/01/2040		1,000,000	1,016,346
Erie, PA, Water Authority Rev., “A”, AGM, 5%, 12/01/2043		1,000,000	1,047,045
Erie, PA, Water Authority Rev., “A”, AGM, 4%, 12/01/2050		995,000	952,389
Erie, PA, Water Authority Rev., “D”, BAM, 4%, 12/01/2041		1,500,000	1,495,960
Florida Capital Region Water Sewer System Rev., 5%, 7/15/2042		1,000,000	1,026,039
Guam Waterworks Authority Rev. (Water and Wastewater System), “A”, 5%, 1/01/2050		205,000	210,596
Philadelphia, PA, Water & Wastewater Rev., “A”, 5%, 10/01/2037		1,000,000	1,048,130
Philadelphia, PA, Water & Wastewater Rev., “A”, 5%, 10/01/2038		1,000,000	1,058,958
Philadelphia, PA, Water & Wastewater Rev., “B”, AGM, 5.5%, 9/01/2053		1,000,000	1,119,841
Pittsburgh, PA, Water & Sewer System Authority Rev., “A”, AGM, 5%, 9/01/2048		1,000,000	1,069,617
			$13,584,728
Total Municipal Bonds			$161,977,370
Bonds – 0.2%
Transportation - Services – 0.2%
Toll Road Investors Partnership II LP, Capital Appreciation, NPFG, 0%, 2/15/2025 (n)	$	270,000	$258,832
Toll Road Investors Partnership II LP, Capital Appreciation, NPFG, 0%, 2/15/2043 (n)		454,602	135,426
Total Bonds			$394,258

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	$	270,845	$165,892
Investment Companies (h) – 0.5%
Money Market Funds – 0.5%
MFS Institutional Money Market Portfolio, 5.39% (v)		747,670	$747,744
Other Assets, Less Liabilities – (1.2)%			(1,954,290)
Net Assets – 100.0%			$161,330,974

(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 $747,744 and $162,537,520, 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 $5,955,129, representing 3.7% 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.
(w)	When-issued security.

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
FNMA	Federal National Mortgage Assn.
NPFG	National Public Finance Guarantee Corp.

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

6/30/24 (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 June 30, 2024 in valuing the fund's assets and liabilities:

Financial Instruments	Level 1	Level 2	Level 3	Total
Municipal Bonds	$—	$162,143,262	$—	$162,143,262
U.S. Corporate Bonds	—	394,258	—	394,258
Mutual Funds	747,744	—	—	747,744
Total	$747,744	$162,537,520	$—	$163,285,264

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	$1,147,173	$8,126,292	$8,525,436	$(113)	$(172)	$747,744

8

Supplemental Information (unaudited) – continued

Affiliated Issuers	Dividend Income	Capital Gain Distributions
MFS Institutional Money Market Portfolio	$22,603	$—

(3) Jurisdiction Weightings

Jurisdiction weighting percentages based on net assets, as of June 30, 2024, are as follows:

Pennsylvania	86.20%
Puerto Rico	3.50%
Illinois	1.70%
New York	1.70%
Alabama	1.50%
California	1.10%
South Carolina	1.10%
Tennessee	0.90%
Guam	0.80%
Texas	0.70%
New Jersey	0.60%
Ohio	0.50%
New Mexico	0.40%
New Hampshire	0.30%
Wisconsin	0.30%
Colorado	0.20%
Michigan	0.20%
Virginia	0.20%
Nevada	0.10%
U.S. Virgin Islands (o)	0.00%

(o) Less than 0.1%.

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

9