Quarterly Report

May 31, 2025

MFS^® Active Intermediate Muni Bond ETF

Principal Listing Exchange: NYSE

EMU-Q1

Portfolio of Investments

5/31/25 (unaudited)

The Portfolio of Investments is a complete list of all securities owned by your fund. It is categorized by jurisdiction.

Issuer		Shares/Par	Value ($)
Municipal Bonds – 99.0%
Alabama – 3.2%
Black Belt Energy Gas District, AL, Gas Project Rev. (Project No. 8), “A”, 4%, 12/01/2052 (Put Date 12/01/2029)	$	165,000	$161,285
Black Belt Energy Gas District, AL, Gas Project Rev., “D”, 5%, 3/01/2055 (Put Date 11/01/2034)		250,000	261,957
Black Belt Energy Gas District, AL, Gas Project Rev., “B”, 5%, 10/01/2055 (Put Date 9/01/2032)		250,000	260,399
Jacksonville, AL, Public Educational Building Authority, Higher Education Facilities Rev. (Jacksonville State University Foundation), “A”, BAM, 5.125%, 8/01/2044		250,000	256,330
Mobile, AL, Industrial Development Board, Pollution Control Rev. (Alabama Power Co.), 3.3%, 7/15/2034 (Put Date 3/12/2026)		150,000	149,981
Southeast Alabama Energy Authority, Cooperative District Energy Supply Rev., “A”, 5%, 11/01/2035		250,000	257,823
Southeast Alabama Energy Authority, Energy Supply Rev., “C”, 5%, 5/01/2055 (Put Date 2/01/2031)		5,000	5,237
			$1,353,012
Alaska – 0.6%
Alaska Municipal Bond Bank Authority, General Obligation & Refunding, “2”, 5%, 12/01/2028	$	260,000	$271,742
Arizona – 1.7%
Arizona Industrial Development Authority, National Education Rev. (Equitable School Revolving Fund LLC), “A”, 5%, 11/01/2038	$	190,000	$192,586
Maricopa County, AZ, Industrial Development Authority, Single Family Mortgage Rev., “A”, 4.15%, 9/01/2040		250,000	235,805
Pima County, AZ, Industrial Development Authority, Single Family Mortgage Rev., “A”, GNMA, 6%, 7/01/2055		250,000	271,209
			$699,600
California – 5.7%
California Community Choice Financing Authority, Clean Energy Project Rev. (Green Bonds), “C”, 5%, 8/01/2055 (Put Date 10/01/2032)	$	250,000	$260,343
California Community Choice Financing Authority, Clean Energy Project Rev. (Green Bonds), “D”, 5%, 2/01/2055 (Put Date 9/01/2032)		250,000	264,705
California Community Choice Financing Authority, Clean Energy Project Rev. (Green Bonds), “F”, 5%, 2/01/2055 (Put Date 11/01/2032)		500,000	529,019
California Community Choice Financing Authority, Clean Energy Project Rev. (Green Bonds), “H”, 5%, 1/01/2056 (Put Date 8/01/2033)		245,000	260,605
California Municipal Finance Authority, COP (Palomar Health), “A”, AGM, 5%, 11/01/2033		170,000	179,299
California Municipal Finance Authority, Refunding Rev. (California Baptist University), “A”, 5%, 11/01/2035		250,000	256,719
California Statewide Communities Development Authority, Infrastructure Program Rev., “C-2”, 5%, 9/02/2028		85,000	88,061
California Statewide Communities Development Authority, Infrastructure Program Rev., “C-2”, 5%, 9/02/2029		100,000	104,218
Central Valley, CA, Energy Authority, Commodity Supply Rev., 5%, 12/01/2055 (Put Date 8/01/2035)		100,000	104,583
Los Angeles, CA, Department of Airports Rev. (Los Angeles International), “A”, 5.25%, 5/15/2038		350,000	358,061
			$2,405,613
Colorado – 5.2%
Adams County, CO, Bromley Park Metropolian District No. 3 General Obligation, AGM, 5%, 12/01/2039	$	225,000	$231,854
Arapahoe County, CO, Cherry Creek School District No. 5, General Obligation, 5.25%, 12/15/2042		500,000	538,216
Bennett, CO, Wastewater Rev., AGM, 5%, 12/01/2044		250,000	259,524
Boulder County, CO, STC Metropolitan District No.2, Limited Tax General Obligation & First Lien Special Refunding Rev., “A-1”, AGM, 5%, 12/01/2036		215,000	225,975
Colorado Health Facilities Authority Rev. (Covenant Living Communities & Services), “A”, 5%, 12/01/2035		245,000	263,323
Denver, CO, Department of Aviation Airport System Rev. “A” , 5%, 11/15/2029		110,000	113,285
Denver, CO, Department of Aviation Airport System Rev. “A” , 5%, 11/15/2034		150,000	158,883
Douglas County, CO, Lanterns Metropolitan District No. 1, AGM, 5%, 12/01/2034		250,000	263,861
Douglas County, CO, Mirabelle Metropolitan District No. 2, “A”, AGM, 5%, 12/01/2040		105,000	107,640
			$2,162,561
Connecticut – 0.9%
Connecticut Higher Education Supplemental Loan Authority, State Supported Rev. (Chesla Loan Program), “B-1”, 5.25%, 11/15/2034	$	250,000	$261,362
Stamford, CT, Housing Authority Rev. (Mozaic Concierge Living Project), “D”, 4.25%, 10/01/2030		100,000	100,145
			$361,507

1

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Delaware – 0.6%
Delaware Housing Authority, Senior Single Family Rev., “A”, GNMA, 5.75%, 1/01/2055	$	245,000	$262,844
District of Columbia – 1.1%
District of Columbia, Housing Finance Agency (Belmont Crossing Phase II), 5%, 3/01/2029 (Put Date 2/01/2028)	$	100,000	$104,457
District of Columbia, Housing Finance Agency, Multi-Family Housing Rev. (2911 Rhode Island Avenue Apartments Project), “A”, FHA, 5%, 3/01/2028		250,000	260,526
Metropolitan Washington, D.C., Airport System Refunding Rev., “A”, 5%, 10/01/2036		115,000	116,841
			$481,824
Florida – 5.0%
Daytona Beach, FL, Halifax Hospital Medical Center Rev., 5%, 6/01/2036	$	125,000	$125,257
Florida Capital Trust Authority, Educational Facilities Rev. (Madrone-Florida Tech Student Housing I, LLC-Florida Institute of Technology Project), “A”, 4.75%, 7/01/2040		100,000	95,473
Florida Higher Educational Facilities Financial Authority Rev. (Nova Southeastern University Project), 5%, 4/01/2036		105,000	105,253
Florida Housing Finance Corp, Multi-Family Mortgage Rev. (The Enclave at Canopy Park), “I”, 3.3%, 7/01/2058 (Put Date 1/01/2028)		250,000	249,765
Hillsborough County, FL, Aviation Authority, Tampa International Airport Rev., “A”, 5%, 10/01/2035		180,000	187,986
Lee County, FL, Airport Rev., “B”, 4%, 10/01/2038		250,000	234,016
Lee County, FL, Industrial Development Authority, Healthcare Facilities Rev. (Shell Point Obligated Group), “C”, 5%, 11/15/2044		200,000	195,991
Miami-Dade County, FL, Aviation Rev., “A”, 5%, 10/01/2038		250,000	249,301
Miami-Dade County, FL, Seaport Refunding Rev., “A”, 5%, 10/01/2036		250,000	259,316
Orlando, FL, Greater Orlando Aviation Authority, Airport Facilities Rev., 5.25%, 10/01/2042		250,000	260,966
Pompano Beach, FL (John Knox Village Project), 5%, 9/01/2039		150,000	147,078
			$2,110,402
Georgia – 3.6%
Atlanta, GA, Urban Residential Finance Authority, Multi-Family Housing Rev. (North Block), 3.4%, 2/01/2029 (Put Date 2/01/2028)	$	100,000	$100,330
DeKalb County, GA, Housing Authority, Multi-Family Housing Rev. (The Avenues of North Decatur), 4.125%, 12/01/2034		120,000	115,919
Fulton County, GA, Development Authority Rev. (Georgia Tech Facilities, Inc.), 5%, 6/15/2044		430,000	435,277
Georgia Main Street Natural Gas, Inc., Gas Supply Rev., “A”, 5%, 5/01/2054 (Put Date 9/01/2031)		210,000	220,512
Georgia Main Street Natural Gas, Inc., Gas Supply Rev., “A”, 5%, 6/01/2055 (Put Date 6/01/2032)		345,000	362,775
Georgia Main Street Natural Gas, Inc., Gas Supply Rev., “E”, 5%, 5/01/2055 (Put Date 12/01/2032)		250,000	260,395
			$1,495,208
Hawaii – 1.0%
Hawaii Airports System Rev., “C”, 5%, 7/01/2043	$	200,000	$201,015
Hawaii Harbor System Rev., “A”, 4%, 7/01/2036		215,000	202,798
			$403,813
Idaho – 0.2%
Idaho Health Facilities Authority Rev. (St. Luke's Health System Project), “C”, 5%, 3/01/2060 (Put Date 3/01/2035)	$	70,000	$76,262
Illinois – 4.7%
Chicago, IL, Board of Education, Dedicated Capital Improvement Tax Bond, 5.25%, 4/01/2033	$	100,000	$108,835
Chicago, IL, Board of Education, Unlimited Tax General Obligation Refunding Dedicated Rev., “B”, 7%, 12/01/2042 (n)		250,000	257,769
Chicago, IL, General Obligation, “A”, 5%, 1/01/2028		130,000	133,755
Chicago, IL, General Obligation, “A”, 5%, 1/01/2041		100,000	98,458
Chicago, IL, Midway Airport Refunding Rev., “A”, 5%, 1/01/2028		250,000	258,577
Cook County, IL, Community College District No. 152 (Hazel Crest), AGM, 5%, 12/01/2036		300,000	320,752
Illinois Finance Authority, Student Housing & Academic Facility Rev. (CHF - Chicago LLC - University of Illinois at Chicago Project), “A”, 5%, 2/15/2037		200,000	197,093
State of Illinois, General Obligation, 5.5%, 5/01/2039		250,000	261,607
Trustees of the University of Illinois, Housing and Auxiliary Facilities System Rev., “A” , BAM, 5%, 4/01/2039		310,000	318,679
			$1,955,525

2

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Indiana – 2.0%
Gary/Chicago International Airport Authority, IN, Development Zone Rev., AGM, 5.25%, 2/01/2042	$	100,000	$104,337
Indiana Finance Authority Rev. (Marquette Project), “A”, 5%, 3/01/2036 (w)		120,000	124,618
Indiana Finance Authority, Health System Rev. (Franciscan Alliance, Inc. Obligated Group), “B”, 5%, 11/01/2041		250,000	250,157
Indiana Finance Authority, Senior Living Rev. (Indiana Masonic Home Project), “A”, 4.3%, 5/01/2029		100,000	100,400
Westfield Washington, IN, Multi-School Building Corp. (Hamilton County), “A”, BAM, 5.25%, 7/15/2043		250,000	262,646
			$842,158
Iowa – 0.6%
Iowa Student Loan Liquidity Corp. Rev., “B”, 5%, 12/01/2033	$	250,000	$262,250
Kentucky – 0.6%
Kentucky Economic Development Finance Authority Rev. (Commonspirit Health), “A-2”, 5%, 8/01/2032	$	125,000	$131,149
Kentucky Economic Development Finance Authority Rev. (Commonspirit Health), “A-2”, 5%, 8/01/2035		125,000	129,177
			$260,326
Louisiana – 2.1%
Juban Crossing, LA, Economic Development District Refunding Rev. (General Infrastructure Projects), “C”, 5%, 9/15/2036	$	250,000	$265,617
Louisiana Local Government, Environmental Facilities & Community Development Authority Rev. (Calcasieu Parish School Project), BAM, 5%, 12/01/2039		250,000	262,005
New Orleans, LA, Aviation Board General Airport Rev. (North Terminal Project), “B”, 5%, 1/01/2036		355,000	357,176
			$884,798
Maine – 1.1%
Maine Finance Authority, Solid Waste Disposal Rev. (Casella Waste Systems, Inc. Project), 4.625%, 12/01/2047 (Put Date 6/01/2035)	$	100,000	$97,366
Maine Finance Authority, Student Loan Rev. (Supplemental Education Loan Program), “A-1”, AGM, 5%, 12/01/2037		70,000	70,394
Maine Health & Higher Educational Facilities Authority Rev. (University of New England), “B”, 4%, 7/01/2037		300,000	287,898
			$455,658
Maryland – 0.4%
Maryland Health & Higher Educational Facilities Authority Rev. (Maryland Institute College of Art), 4%, 6/01/2042	$	210,000	$180,923
Massachusetts – 3.0%
Dover, MA, General Obligation Municipal Purpose Loan , 5%, 6/15/2039	$	115,000	$121,960
Massachusetts Development Finance Agency Rev. (Lahey Health System Obligated Group), “F”, 5%, 8/15/2029		250,000	250,473
Massachusetts Development Finance Agency Rev. (Newbridge on the Charles, Inc.), 5%, 10/01/2037 (n)		125,000	125,710
Massachusetts Development Finance Agency Rev. (Wentworth Institute of Technology), 5%, 10/01/2046		125,000	116,796
Massachusetts Development Finance Agency, Refunding Rev. (Lasell Village, Inc.), 5%, 7/01/2034		195,000	206,780
Massachusetts Educational Financing Authority, Education Loan Rev., “B”, 5%, 7/01/2029		300,000	311,979
Massachusetts Port Authority Rev., “A”, 5%, 7/01/2039		105,000	106,882
			$1,240,580
Michigan – 0.6%
Wayne County, MI, Airport Authority Rev. (Detroit Metropolitan Wayne County Airport), “B”, 5%, 12/01/2042	$	250,000	$247,017
Minnesota – 3.1%
Duluth, MN, Economic Development Authority, Health Care Facilities Rev. (Essentia Health), “A”, 5%, 2/15/2037	$	150,000	$152,285
Edina, MN, General Obligation Capital Improvement Plan and Sales Tax Rev., “B”, 4%, 2/01/2042		250,000	239,814
Minneapolis, MN, Health Care Systems Rev. (Fairview Health Services), “A”, 5%, 11/15/2035		160,000	163,215
Minnesota General Obligation State Trunk Highway Rev., “B”, 4%, 8/01/2041		500,000	487,164
Minnesota Housing Finance Agency, Residential Housing Finance Rev., “F”, 5.75%, 7/01/2053		240,000	253,805
			$1,296,283
Missouri – 0.6%
Springfield, MO, Public Utility Refunding Rev., 4%, 8/01/2036	$	250,000	$240,580

3

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
New Hampshire – 2.2%
National Finance Authority, NH, Affordable Housing Certificates, “1-A”, 4.75%, 6/20/2041 (Put Date 6/01/2035) (w)	$	250,000	$249,700
National Finance Authority, NH, Municipal Certificates, “A-1”, 4.087%, 1/20/2041		99,856	92,879
National Finance Authority, NH, Municipal Certificates, “A-2”, 4.087%, 1/20/2041		99,857	88,434
New Hampshire Business Finance Authority, Water Facility Rev. (Pennichuck Water Works, Inc. Project), “A”, 5.75%, 4/01/2035		105,000	113,725
New Hampshire Health & Education Facilities Authority Rev. (Dartmouth Hitchcock Obligated Group), “A”, 5%, 8/01/2038		250,000	252,069
New Hampshire Health & Education Facilities Authority, Education Loan Rev. (Granite Advance Corp. Issue), “B”, 5%, 10/01/2035		125,000	133,687
			$930,494
New Jersey – 2.1%
New Jersey Economic Development Authority, Dock & Wharf Facility Rev. (Repauno Port & Rail Terminal Project), 6.375%, 1/01/2035	$	100,000	$101,196
New Jersey Tobacco Settlement Financing Corp., “A”, 5.25%, 6/01/2046		215,000	215,822
New Jersey Transportation Trust Fund Authority, “A”, 4.25%, 6/15/2040		210,000	199,943
New Jersey Transportation Trust Fund Authority, “CC”, 5%, 6/15/2042		250,000	257,004
Passaic County, NJ, Improvement Authority, Charter School Rev. (Paterson Charter School for Science & Technology Inc., Project), 4.125%, 7/01/2033		100,000	99,052
			$873,017
New Mexico – 1.4%
New Mexico Municipal Energy Acquisition Authority, Gas Supply Refunding Rev., 5%, 6/01/2054 (Put Date 11/01/2030)	$	100,000	$104,559
Santa Fe County, NM, Multi-Family Housing Rev. (Cresta Ranch Apartments), 3.29%, 12/10/2049 (Put Date 6/01/2028)		500,000	498,645
			$603,204
New York – 6.8%
New York Dormitory Authority Rev. (New School), “B”, 5%, 7/01/2042	$	250,000	$253,129
New York Dormitory Authority Rev. (White Plains Hospital Obligated Group), AGM, 5.25%, 10/01/2044		175,000	183,008
New York Dormitory Authority Rev., State Sales Tax Rev., “B”, 5%, 3/15/2042		95,000	100,086
New York Housing Finance Agency 320 West 38th Street Housing Rev., “A”, FHLMC, 3.57%, 5/01/2042 (Put Date 11/01/2031)		250,000	244,075
New York Transportation Development Corp., Special Facilities Rev. (Delta Airlines, Inc. LaGuardia Airport Terminals C&D Redevelopment Project), 5%, 1/01/2029		120,000	122,233
New York Transportation Development Corp., Special Facilities Rev. (John F. Kennedy International Airport New Terminal One Project), AGM, 5.5%, 6/30/2042		245,000	255,346
New York Transportation Development Corp., Special Facilities Rev. (Terminal 4 John F. Kennedy International Airport Project), 5%, 12/01/2032		200,000	211,246
New York, NY, Housing Development Corp., Multi-Family Housing Rev., “F-2”, 3.4%, 11/01/2064 (Put Date 1/02/2029)		500,000	496,722
New York, NY, Housing Development Corp., Multi-Family Mortgage Rev. (8 Spruce Street), “E”, 4.375%, 12/15/2031		100,000	101,478
New York, NY, Transitional Finance Authority Rev., “D”, 5%, 5/01/2042		250,000	261,401
New York, NY, Transitional Finance Authority Rev., “D-1”, 4%, 11/01/2042		250,000	229,901
Rockland County, NY, Solid Waste Management Authority, Special Obligation Rev. (Animal Shelter Project), “A”, 5.5%, 12/15/2044		340,000	367,760
			$2,826,385
North Carolina – 2.2%
Cumberland County, NC, Industrial Facilities and Pollution Control Financing Authority, Solid Waste Disposal Rev. (Project Aero), 3.75%, 12/01/2027 (Put Date 11/01/2025)	$	15,000	$15,005
Greater Asheville, NC, Regional Airport Authority System Rev., “A”, AGM, 5.25%, 7/01/2038		500,000	526,733
North Carolina Medical Care Commission, Health Care Facilities First Mortgage Rev. (Lutheran Services for the Aging), “A”, 4%, 3/01/2030		125,000	123,273
Raleigh, NC, Housing Authority, Multi-Family Housing Rev. (919 at Cross Link), “B”, 5%, 8/01/2028 (Put Date 8/01/2027)		250,000	259,123
			$924,134
North Dakota – 0.6%
Grand Forks, ND, Health Care Systems Rev. (Altru Health System), 5%, 12/01/2030	$	120,000	$125,446
Horace, ND, Refunding Improvement, “C”, 5.5%, 5/01/2038		125,000	129,104
			$254,550

4

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Ohio – 3.5%
Buckeye, OH, Tobacco Settlement Financing Authority Senior Asset-Backed Refunding, 2020A-2, “1”, 5%, 6/01/2033	$	250,000	$259,929
Columbus, OH, Metropolitan Housing Authority, General Rev. (Orchards Project and the Eden Park Project), 5%, 12/01/2034		250,000	256,883
Columbus, OH, Regional Airport Authority Rev. (John Glenn Columbus International Airport), “A”, AGM, 5%, 1/01/2035		100,000	105,739
Cuyahoga County, OH, Hospital Rev. (MetroHealth System), 5.5%, 2/15/2052		350,000	341,687
Erie & Sandusky Counties, OH, Margaretta Local School District (Ohio Certificates of Participation School Facilities Project), BAM, 5.5%, 10/01/2037		145,000	157,232
Hamilton County, OH, Various Purpose General Obligation, 4%, 12/17/2025		100,000	100,354
Ohio State Healthcare Facility Rev. (Otterbein Homes Obligated Group), 4%, 7/01/2036		240,000	233,964
			$1,455,788
Oklahoma – 1.5%
Cleveland County, OK, Home Loan Authority, Single Family Mortgage Rev., “A”, GNMA, 5.75%, 1/01/2056	$	250,000	$271,084
Oklahoma Turnpike Authority, Turnpike System Refunding Second Senior Rev., “B”, 5%, 1/01/2037 (w)		100,000	108,355
Tulsa, OK, Airport Improvement Trust General Rev., “A”, BAM, 5%, 6/01/2028		245,000	255,203
			$634,642
Pennsylvania – 10.4%
Adams County, PA, General Authority Rev. (Brethren Home Community Project), “A”, 5%, 6/01/2034	$	125,000	$129,855
Allegheny County, PA, Airport Authority Rev. (Pittsburgh International Airport), “A”, AGM, 5%, 1/01/2036		215,000	228,601
Allegheny County, PA, Hospital Development Authority Rev. (Allegheny Health Network Obligated Group), “A”, 5%, 4/01/2036		245,000	250,022
DuBois, PA, Hospital Rev. (Penn Highlands Healthcare), 5%, 7/15/2036		140,000	136,162
Erie, PA, Higher Education Building Authority Rev. (AICUP Financing Program-Gannon University Project), “XX1”, 4%, 5/01/2033		100,000	97,944
Lancaster, PA, Municipal Authority, Healthcare Facilities Rev. (Luthercare Project), “A”, 4%, 12/01/2035		240,000	232,831
Pennsylvania Economic Development Financing Authority, (UPMC) Rev., “A”, 5%, 3/15/2060 (Put Date 3/15/2035)		280,000	293,891
Pennsylvania Economic Development Financing Authority, Private Activity Rev. (PennDOT Major Bridges Package One Project), AGM, 5.5%, 6/30/2042		500,000	519,345
Pennsylvania Economic Development Financing Authority, Private Activity Rev. (Pennsylvania Rapid Bridge Replacement Project), 5%, 12/31/2034		500,000	502,050
Pennsylvania Economic Development Financing Authority, Solid Waste Disposal Rev. (Republic Services, Inc. Project), “A”, VRDN, 4.25%, 4/01/2034 (Put Date 7/15/2025)		300,000	300,154
Pennsylvania Economic Development Financing Authority, Solid Waste Disposal Rev. (Waste Management, Inc. Project), 4.1%, 8/01/2045 (Put Date 8/01/2025)		100,000	100,046
Pennsylvania Higher Educational Assistance Agency, Education Loan Rev., “1A”, 4.125%, 6/01/2045		135,000	128,286
Pennsylvania Higher Educational Assistance Agency, Education Loan Rev., “A-1”, 4.75%, 6/01/2046 (w)		105,000	103,219
Pennsylvania Housing Finance Agency, Multi-Family Housing Development (Country Commons Apartments), FNMA, 3.6%, 8/01/2035		182,850	171,924
Pennsylvania Public School Building Authority, College Rev. (Delaware County Community College Project), BAM, 5.25%, 10/01/2044		265,000	271,202
Pennsylvania School District Authority Rev. (William Penn School District Project), “B”, BAM, 5%, 3/15/2043		100,000	101,997
Philadelphia, PA, Authority for Industrial Development, Hospital Rev. (Children's Hospital of Philadelphia Project), 5%, 7/01/2033		250,000	256,700
Philadelphia, PA, Hospitals and Higher Education Facilities Authority Rev. (Temple University Health System Obligated Group), AGM, 5%, 7/01/2036		115,000	121,025
Philadelphia, PA, Housing Authority, General Rev. (PHA Headquarters Project), 5%, 5/01/2039		250,000	252,922
Southeastern Pennsylvania Transportation Authority Rev. (Asset Improvement Program), 5.25%, 6/01/2047		135,000	139,799
			$4,337,975
Puerto Rico – 2.0%
Commonwealth of Puerto Rico, General Obligation Restructured, “A-1”, 5.625%, 7/01/2027	$	125,000	$128,280
Puerto Rico Electric Power Authority Rev., “VV”, NPFG, 5.25%, 7/01/2030		325,000	323,594
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., “A-2”, 4.329%, 7/01/2040		250,000	232,925
Puerto Rico Sales Tax Financing Corp., Restructured Sales Tax Rev., Capital Appreciation, “A-1”, 0%, 7/01/2033		201,000	142,127
			$826,926
Rhode Island – 1.9%
Providence, RI, Public Buildings Authority Rev. (Capital Improvement Program Projects), “A”, AGM, 5%, 9/15/2035	$	375,000	$382,484
Rhode Island Health & Educational Building Corp., Hospital Financing Rev. (Lifespan Obligated Group), 4%, 5/15/2036		125,000	117,482
Rhode Island Student Loan Authority, Education Loan Rev., “B”, 5%, 12/01/2033		250,000	259,366

5

Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Rhode Island – continued
Rhode Island Student Loan Authority, Education Loan Rev., “B”, 4.125%, 12/01/2043	$	65,000	$58,521
			$817,853
South Carolina – 1.5%
Florence County, SC, Special Source Rev. (Savannah Grove Infrastructure Projects), 5%, 12/01/2036	$	150,000	$161,427
South Carolina Jobs & Economic Development Authority, Economic Development Rev. (Foothill Affordable Housing Foundation - Paddock Club and Fairway Projects), FHLMC, 4%, 3/01/2062 (Put Date 3/01/2035)		100,000	95,519
South Carolina Jobs & Economic Development Authority, Solid Waste Disposal Rev. (Enerra South Carolina Project), 3.7%, 12/15/2027 (Put Date 12/01/2026)		105,000	104,534
South Carolina Public Service Authority Rev. (Santee Cooper), “A”, 5%, 12/01/2038		125,000	124,818
South Carolina Public Service Authority Rev. (Santee Cooper), “B”, 5%, 12/01/2032		125,000	126,016
			$612,314
Texas – 7.3%
Arlington, TX, Higher Education Finance Corp. Education Rev. (Riverwalk Education Foundation, Inc.), 5%, 8/15/2042	$	250,000	$258,071
Celina, TX, Special Assessment Refunding & Improvement Rev. (The Lakes at Mustang Ranch Public Improvement District Major Improvement Area and Phases #2-7 Project), AGM, 5%, 9/01/2035		250,000	263,183
EP Cimarron Ventanas, TX, Residential Development Rev. (Home Essential Function Housing Program), 4%, 12/01/2034		250,000	241,237
EP Cimarron Ventanas, TX, Residential Development Rev. (Lifestyles at Los Paseos), 4.125%, 12/01/2039		20,000	18,656
Galveston, TX, Wharves & Terminal Rev., 5.25%, 8/01/2037		250,000	259,274
Houston, TX, Airport System Special Facilities Rev. (United Airlines, Inc. Terminal Improvement Project), “B”, 5.25%, 7/15/2034		150,000	153,593
Houston, TX, Redevelopment Authority Tax Increment Contract Rev., AGM, 5%, 9/01/2037		150,000	159,528
Lower Colorado River Authority, Transmission Contract Refunding Rev. (LCRA Transmission Services Corp. Project), 5%, 5/15/2046		230,000	231,293
Mission, TX, Economic Development Corp., Solid Waste Disposal Rev. (Graphic Packaging International, LLC Project), 5%, 12/01/2064 (Put Date 6/01/2030)		100,000	102,128
Mission, TX, Economic Development Corp., Solid Waste Disposal Rev. (Republic Services, Inc. Project), 4.1%, 1/01/2026 (Put Date 8/01/2025)		100,000	100,048
New Hope, TX, Cultural Education Facilities Finance Corp., Retirement Facility Rev. (Bella Vida Forefront Living Project), “B-3”, 4.25%, 10/01/2030		100,000	99,496
New Hope, TX, Cultural Education Facilities Finance Corp., Retirement Facility Rev. (Morningside Ministries Project), “A”, 5%, 1/01/2035		150,000	144,356
New Hope, TX, Cultural Education Facilities Finance Corp., Retirement Facility Rev. (Westminster Project), 5%, 11/01/2035		160,000	168,250
Tarrant County, TX, Cultural Education Facilities Finance Refunding Rev. (Trinity Terrace Project), 5%, 10/01/2038		135,000	138,908
Texas Department of Housing & Community Affairs, Residential Mortgage Rev., GNMA, 5.75%, 1/01/2056		250,000	271,614
Texas Municipal Gas Acquisition & Supply Corp. V, Gas Supply Rev., 5%, 1/01/2055 (Put Date 1/01/2034)		250,000	263,152
Texas Private Activity Surface Transportation Corp. Rev. (NTE Mobility Partners Segments 3 LLC), 5.375%, 6/30/2038		160,000	165,376
			$3,038,163
Utah – 1.1%
Salt Lake City, UT, Airport Rev. (Salt Lake City International Airport), “A”, 5%, 7/01/2042	$	295,000	$290,860
Utah Charter School Finance Authority, Charter School Rev. (Lakeview Academy), 5%, 4/15/2040		150,000	155,007
			$445,867
Vermont – 0.6%
Vermont Student Assistance Corp., Education Loan Rev., “A”, 5%, 6/15/2033	$	250,000	$259,672
Virginia – 1.4%
Chesapeake, VA, Hospital Authority Facility Rev. (Chesapeake Regional Medical Center), 4%, 7/01/2036	$	320,000	$311,153
Virginia Small Business Financing Authority Rev. (I-495 HOT Lanes Project), 5%, 12/31/2038		125,000	128,639
Virginia Small Business Financing Authority Rev. (I-495 HOT Lanes Project), 5%, 12/31/2040		125,000	127,154
			$566,946
Washington – 2.1%
Kenmore, WA, Limited Tax General Obligation , 5%, 12/01/2044	$	250,000	$260,523
Seattle, WA, Port Intermediate Lien Refunding Rev., “A”, 5%, 5/01/2033		250,000	253,569
Seattle, WA, Port Intermediate Lien Refunding Rev., “A”, 5%, 5/01/2036		250,000	252,196

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Portfolio of Investments (unaudited) – continued

Issuer		Shares/Par	Value ($)
Municipal Bonds – continued
Washington – continued
Vancouver, WA, Housing Authority, Multi-Family Rev. (Cascara Project), “A”, 5%, 12/01/2042	$	125,000	$119,686
			$885,974
Wisconsin – 2.8%
Wisconsin Health & Educational Facilities Authority Rev. (Ascension Senior Credit Group), “A”, 4%, 11/15/2032	$	175,000	$175,244
Wisconsin Public Finance Authority Rev., Taxable (Kahala Nui Project), 5%, 11/15/2037		150,000	157,759
Wisconsin Public Finance Authority, Air Cargo Obligated Group Rev. (AFCO Airport Real Estate Group), 5%, 7/01/2033		310,000	323,911
Wisconsin Public Finance Authority, Education Rev. (Pine Lake Preparatory), 4.95%, 3/01/2030 (n)		120,000	120,027
Wisconsin Public Finance Authority, Education Rev. (Triad Educational Services, Inc.), 5%, 6/15/2032		125,000	129,414
Wisconsin Public Finance Authority, Student Housing Facilities Rev. (Campus Real Estate Holding Corp. LLC Project), “A”, 5%, 6/01/2035		145,000	149,486
Wisconsin Public Finance Authority, Student Housing Rev. (KSU Bixby Real Estate Foundation LLC Project), “B”, 5.25%, 6/15/2035		100,000	105,965
			$1,161,806
Total Municipal Bonds			$41,406,196
Mutual Funds – 1.3%
Money Market Funds – 1.3%
State Street Institutional U.S. Government Money Market Fund - Premier Class, 4.27% (j)		552,786	$552,786
Other Assets, Less Liabilities – (0.3)%			(121,705)
Net Assets – 100.0%			$41,837,277

(j)	The rate quoted is the annualized seven-day yield of the fund at period end.
(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 $503,506, representing 1.2% of net assets.
(w)	When-issued security.

The following abbreviations are used in this report and are defined:
AGM	Assured Guaranty Municipal
BAM	Build America Mutual
COP	Certificate of Participation
FHA	Federal Housing Administration
FHLMC	Federal Home Loan Mortgage Corp.
FNMA	Federal National Mortgage Assn.
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.

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Supplemental Information

5/31/25 (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. Pricing services generally value debt instruments assuming orderly transactions of institutional round lot sizes, but a fund may hold or transact in such securities in smaller, odd lot sizes. In instances where a fund holds an odd lot size position in a debt instrument, such position will typically be valued using the pricing agent’s institutional round lot price for the debt instrument. Odd lots may trade at lower prices than institutional round lots, and the fund may receive different prices when it sells odd lot positions than it would receive for sales of institutional round lot positions. 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 May 31, 2025 in valuing the fund's assets and liabilities:

Financial Instruments	Level 1	Level 2	Level 3	Total
Municipal Bonds	$—	$41,406,196	$—	$41,406,196
Investment Companies	552,786	—	—	552,786
Total	$552,786	$41,406,196	$—	$41,958,982

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

8