{
  "page": "compare",
  "query": {
    "a": "MPOAX",
    "b": "MFSMX"
  },
  "retrieved_at": "2026-07-07T18:17:40+00:00",
  "disclaimer": "Informational only — not investment advice. FundWatcher presents publicly available data and makes no recommendation to buy or sell any security. Verify all figures against the source filing before relying on them.",
  "attribution": "Data sourced from U.S. SEC EDGAR filings (Forms N-PORT, N-CEN, and prospectus Risk/Return summaries). FundWatcher is not affiliated with the SEC.",
  "terms": {
    "notice": "Use of this data is subject to the FundWatcher Terms of Service. Information may be used only for personal, non-commercial research and may not be redistributed.",
    "url": "https://fundwatcher.app/terms/"
  },
  "fund_a": {
    "name": "MFS California Municipal Bond Fund",
    "ticker": "MPOAX",
    "slug": "MPOAX",
    "series_id": "S000002530",
    "html_url": "https://fundwatcher.app/funds/MPOAX/"
  },
  "fund_b": {
    "name": "MFS Maryland Municipal Bond Fund",
    "ticker": "MFSMX",
    "slug": "MFSMX",
    "series_id": "S000002533",
    "html_url": "https://fundwatcher.app/funds/MFSMX/"
  },
  "overlap": {
    "coverage_a_by_b": "0.08102764985310461439531760559",
    "coverage_b_by_a": "0.08102764985310461439531760559",
    "shared_count": 38,
    "as_of": {
      "a": "2026-03-31",
      "b": "2026-03-31"
    },
    "a_top": [
      {
        "name": "MFS Institutional Money Market Portfolio, Class A",
        "value": "33164381.09",
        "weight": "0.04157409",
        "shared": true
      },
      {
        "name": "California Community Choice Financing Authority, Series C",
        "value": "9338921.10",
        "weight": "0.01170705",
        "shared": false
      },
      {
        "name": "CALIFORNIA COMMUNITY VAR",
        "value": "8035752.75",
        "weight": "0.01007343",
        "shared": false
      },
      {
        "name": "LOS ANGELES HSG-A",
        "value": "7919212.00",
        "weight": "0.00992734",
        "shared": false
      },
      {
        "name": "CALIFORNIA MUNICIPAL FINANCE AUTHORITY",
        "value": "7897030.95",
        "weight": "0.00989953",
        "shared": false
      },
      {
        "name": "OAKLAND UNIF SCH D-A",
        "value": "7361357.50",
        "weight": "0.00922802",
        "shared": false
      },
      {
        "name": "Inglewood Joint Powers Authority, Series 2025",
        "value": "6330975.60",
        "weight": "0.00793636",
        "shared": false
      },
      {
        "name": "California Housing Finance Agency, Series 2026 ISSUE A",
        "value": "5891413.20",
        "weight": "0.00738534",
        "shared": false
      },
      {
        "name": "CALIFORNIA ST HLTH FACS FING AUTH REVENUE",
        "value": "5774298.45",
        "weight": "0.00723852",
        "shared": false
      },
      {
        "name": "CALIFORNIA COMMUNITY VAR",
        "value": "5409991.00",
        "weight": "0.00678184",
        "shared": true
      },
      {
        "name": "San Francisco (City & County of), CA Airport Commission (San Francisco International Airport), Second Series 2023 C, Ref. RB",
        "value": "5339977.00",
        "weight": "0.00669407",
        "shared": false
      },
      {
        "name": "San Francisco Community College District, Series B",
        "value": "5309297.00",
        "weight": "0.00665561",
        "shared": false
      },
      {
        "name": "OAKLAND-D",
        "value": "5297019.50",
        "weight": "0.00664022",
        "shared": false
      },
      {
        "name": "California (State of) Community Choice Financing Authority (Green Bonds), Series 2023 C, RB",
        "value": "5289029.00",
        "weight": "0.00663020",
        "shared": true
      },
      {
        "name": "California (State of) Community Choice Financing Authority (Green Bonds), Series 2023, RB",
        "value": "5232771.50",
        "weight": "0.00655968",
        "shared": false
      },
      {
        "name": "IRVINE CMNTY FACS DT",
        "value": "5226065.50",
        "weight": "0.00655127",
        "shared": false
      },
      {
        "name": "San Diego County Regional Airport Authority, Series 2025 B",
        "value": "5203924.00",
        "weight": "0.00652352",
        "shared": false
      },
      {
        "name": "SAN LUIS OBISPO PUBLIC FINANCI SLOFIN 12/53 FIXED 5",
        "value": "5185679.00",
        "weight": "0.00650064",
        "shared": false
      },
      {
        "name": "CALIFORNIA ST HLTH FACS FING AUTH REVENUE",
        "value": "5167421.00",
        "weight": "0.00647776",
        "shared": false
      },
      {
        "name": "PUERTO RICO SALES TAX FING COR REGD OID B/E 5.00000000",
        "value": "5082159.40",
        "weight": "0.00637088",
        "shared": true
      },
      {
        "name": "Mt. San Antonio Community College District, Series 2013A",
        "value": "5075566.50",
        "weight": "0.00636261",
        "shared": false
      },
      {
        "name": "CA STWD(ENLOE HLTH SYST)/AGM 5.38% 8/15/57",
        "value": "5057092.00",
        "weight": "0.00633945",
        "shared": false
      },
      {
        "name": "CA MUNI FIN AUTH-A",
        "value": "5004730.50",
        "weight": "0.00627381",
        "shared": false
      },
      {
        "name": "California Housing Finance Agency, Series 2024 ISSUE DD",
        "value": "4960470.00",
        "weight": "0.00621833",
        "shared": false
      },
      {
        "name": "CALIFORNIA HSG FIN AGY LTD OBLIG MF HSG REVENUE",
        "value": "4913372.00",
        "weight": "0.00615929",
        "shared": false
      },
      {
        "name": "CALIFORNIA HSG FIN AGY LTD OBLIG MF HSG REVENUE",
        "value": "4913372.00",
        "weight": "0.00615929",
        "shared": false
      },
      {
        "name": "CALIFORNIA HSG FIN AGY LTD OBLIG MF HSG REVENUE",
        "value": "4911349.50",
        "weight": "0.00615675",
        "shared": false
      },
      {
        "name": "North Lake Tahoe Public Financing Authority 5.50% 12/01/2047",
        "value": "4779932.79",
        "weight": "0.00599201",
        "shared": false
      },
      {
        "name": "SANTA CLARA CY 3% 5/1/2039",
        "value": "4749264.98",
        "weight": "0.00595357",
        "shared": false
      },
      {
        "name": "New Hampshire Business Finance Authority, Series 4, Class A",
        "value": "4745309.41",
        "weight": "0.00594861",
        "shared": false
      },
      {
        "name": "Clovis Unified School District, Series C",
        "value": "4709697.50",
        "weight": "0.00590397",
        "shared": false
      },
      {
        "name": "Alameda Corridor Transportation Authority, Series C",
        "value": "4657024.28",
        "weight": "0.00583794",
        "shared": false
      },
      {
        "name": "UNIV OF CA REGENTS -P",
        "value": "4520440.00",
        "weight": "0.00566672",
        "shared": false
      },
      {
        "name": "LOS ANGELES DEPT ARPT",
        "value": "4460673.00",
        "weight": "0.00559179",
        "shared": false
      },
      {
        "name": "CALIFORNIA ST MUNI FIN AUTH RE CASFIN 01/42 FIXED 5",
        "value": "4318553.63",
        "weight": "0.00541364",
        "shared": false
      },
      {
        "name": "CALIFORNIA CMNTY CHOICE FING A REGD B/E 5.25000000",
        "value": "4290378.80",
        "weight": "0.00537832",
        "shared": false
      },
      {
        "name": "CALIFORNIA COMMUNITY VAR",
        "value": "4284094.80",
        "weight": "0.00537044",
        "shared": false
      },
      {
        "name": "CA ST UNIV-A-REF",
        "value": "4276758.00",
        "weight": "0.00536124",
        "shared": false
      },
      {
        "name": "LOS ANGELES CA DEPT OF ARPTS ARPT REVENUE",
        "value": "4264779.42",
        "weight": "0.00534623",
        "shared": false
      },
      {
        "name": "San Francisco (City & County of), CA Airport Commission (San Francisco International Airport), Second Series 2024, Ref. RB",
        "value": "4256294.40",
        "weight": "0.00533559",
        "shared": false
      },
      {
        "name": "Ceres Unified School District, Series 2025A",
        "value": "4169338.00",
        "weight": "0.00522658",
        "shared": false
      },
      {
        "name": "Los Angeles Department of Airports, California, Revenue Bonds, Los Angeles International Airport, Refunding Subordinate Green Series 2025A",
        "value": "4167433.20",
        "weight": "0.00522420",
        "shared": false
      },
      {
        "name": "Kerman Public Financing Authority, Series 2025",
        "value": "4151228.00",
        "weight": "0.00520388",
        "shared": false
      },
      {
        "name": "San Francisco (City & County of), CA Airport Commission (San Francisco International Airport), Series 2016, RB",
        "value": "4000098.00",
        "weight": "0.00501443",
        "shared": false
      },
      {
        "name": "CA ST MFA COP 5.25% 11/1/2052",
        "value": "3994617.20",
        "weight": "0.00500756",
        "shared": false
      },
      {
        "name": "CA MUNI FIN AUTH-A",
        "value": "3992080.80",
        "weight": "0.00500438",
        "shared": false
      },
      {
        "name": "BEVERLY HILLS USD CAB",
        "value": "3985423.87",
        "weight": "0.00499603",
        "shared": false
      },
      {
        "name": "REPUBLIC SERVICES INC (MPT) 3.875% 03-01-54",
        "value": "3972416.40",
        "weight": "0.00497973",
        "shared": false
      },
      {
        "name": "INDIO PUB FING AUTH-A",
        "value": "3933807.70",
        "weight": "0.00493133",
        "shared": false
      },
      {
        "name": "GOLDEN ST TOBACCO SECURITIZATI REGD B/E 5.00000000",
        "value": "3914510.80",
        "weight": "0.00490714",
        "shared": false
      }
    ],
    "b_top": [
      {
        "name": "MFS Institutional Money Market Portfolio, Class A",
        "value": "5117103.28",
        "weight": "0.03287827",
        "shared": true
      },
      {
        "name": "MARYLAND ST ECON DEV CORP LEASE REVENUE",
        "value": "2066416.60",
        "weight": "0.01327708",
        "shared": false
      },
      {
        "name": "Maryland Economic Development Corp., Series 2024",
        "value": "1956308.20",
        "weight": "0.01256962",
        "shared": false
      },
      {
        "name": "Montgomery (County of), MD, Series 2017, GO Bonds",
        "value": "1900000.00",
        "weight": "0.01220783",
        "shared": false
      },
      {
        "name": "MARYLAND ST STD 5% 5/1/2035",
        "value": "1785164.72",
        "weight": "0.01146999",
        "shared": false
      },
      {
        "name": "PUERTO RICO SALES TAX FING COR REGD OID B/E 5.00000000",
        "value": "1727325.78",
        "weight": "0.01109837",
        "shared": true
      },
      {
        "name": "County of Prince George's, Series 2025 A",
        "value": "1607726.55",
        "weight": "0.01032992",
        "shared": false
      },
      {
        "name": "Washington Metropolitan Area Transit Authority Dedicated",
        "value": "1607187.60",
        "weight": "0.01032646",
        "shared": false
      },
      {
        "name": "Maryland Stadium Authority, Series 2024",
        "value": "1571792.40",
        "weight": "0.01009904",
        "shared": false
      },
      {
        "name": "County of Anne Arundel, Series 2025",
        "value": "1562597.40",
        "weight": "0.01003996",
        "shared": false
      },
      {
        "name": "MD HLTH & HGR EDL-A",
        "value": "1561890.15",
        "weight": "0.01003541",
        "shared": false
      },
      {
        "name": "Maryland Health & Higher Educational Facilities Authority",
        "value": "1554150.45",
        "weight": "0.00998568",
        "shared": false
      },
      {
        "name": "PRINCE GEO COP 5% 10/1/48",
        "value": "1524666.75",
        "weight": "0.00979625",
        "shared": false
      },
      {
        "name": "Maryland Community Development Administration, Series 2025 F-1",
        "value": "1506350.25",
        "weight": "0.00967856",
        "shared": false
      },
      {
        "name": "MARYLAND STADIUM AUTHORITY",
        "value": "1492435.35",
        "weight": "0.00958915",
        "shared": false
      },
      {
        "name": "WASHINGTON SUBURBAN SANITARY COMMISSION",
        "value": "1461898.35",
        "weight": "0.00939295",
        "shared": false
      },
      {
        "name": "COUNTY OF BALTIMORE MD",
        "value": "1457850.60",
        "weight": "0.00936694",
        "shared": false
      },
      {
        "name": "County of Howard",
        "value": "1424096.70",
        "weight": "0.00915007",
        "shared": false
      },
      {
        "name": "MARYLAND ST HLTH & HGR EDUCTNL FACS AUTH REVENUE",
        "value": "1406792.17",
        "weight": "0.00903888",
        "shared": false
      },
      {
        "name": "Maryland Health & Higher Educational Facilities Authority, Series 2004",
        "value": "1396223.21",
        "weight": "0.00897098",
        "shared": false
      },
      {
        "name": "County of Anne Arundel, Series 2023",
        "value": "1393211.60",
        "weight": "0.00895163",
        "shared": false
      },
      {
        "name": "City of Baltimore, Series 2019 A",
        "value": "1392087.02",
        "weight": "0.00894440",
        "shared": false
      },
      {
        "name": "Maryland Community Development Administration Department of Housing and Community Development, Residential Revenue Bonds, Taxable Series 2019D",
        "value": "1391971.66",
        "weight": "0.00894366",
        "shared": false
      },
      {
        "name": "MARYLAND ST STA 4% 6/1/2046",
        "value": "1314577.29",
        "weight": "0.00844639",
        "shared": false
      },
      {
        "name": "MARYLAND HEALTH & HIGHER EDUCATIONAL FACILITIES AUTHORITY",
        "value": "1288038.33",
        "weight": "0.00827587",
        "shared": false
      },
      {
        "name": "Maryland Health & Higher Educational Facilities Authority",
        "value": "1260651.72",
        "weight": "0.00809990",
        "shared": false
      },
      {
        "name": "MONTGOMERY CNTY MD REVENUE REGD B/E 5.00000000",
        "value": "1240317.19",
        "weight": "0.00796925",
        "shared": false
      },
      {
        "name": "Maryland Community Development Administration Local Government Infrastructure",
        "value": "1230218.13",
        "weight": "0.00790436",
        "shared": false
      },
      {
        "name": "MD CMNTY DEV-D-1",
        "value": "1190841.13",
        "weight": "0.00765136",
        "shared": false
      },
      {
        "name": "Washington Metropolitan Area Transit Authority, Series 2018, RB",
        "value": "1155596.68",
        "weight": "0.00742491",
        "shared": false
      },
      {
        "name": "MD HEFA 4% 7/1/2048",
        "value": "1108365.50",
        "weight": "0.00712144",
        "shared": false
      },
      {
        "name": "County of Montgomery",
        "value": "1107250.70",
        "weight": "0.00711428",
        "shared": false
      },
      {
        "name": "MD CMNTY DEPT ADMIN-B",
        "value": "1097910.15",
        "weight": "0.00705426",
        "shared": false
      },
      {
        "name": "Maryland Health & Higher Educational Facilities Authority",
        "value": "1094371.76",
        "weight": "0.00703153",
        "shared": false
      },
      {
        "name": "CALIFORNIA COMMUNITY VAR",
        "value": "1081998.20",
        "weight": "0.00695203",
        "shared": true
      },
      {
        "name": "MD TRANSPRTN-A-REF",
        "value": "1080306.40",
        "weight": "0.00694116",
        "shared": false
      },
      {
        "name": "Montgomery County Housing Opportunities Commission, Series 2023 C",
        "value": "1076666.80",
        "weight": "0.00691777",
        "shared": false
      },
      {
        "name": "Maryland Department of Housing & Community Development, Series 2024 E",
        "value": "1076506.43",
        "weight": "0.00691674",
        "shared": false
      },
      {
        "name": "MD ECON DEV CORP-A",
        "value": "1072393.30",
        "weight": "0.00689031",
        "shared": false
      },
      {
        "name": "County of Prince George's",
        "value": "1040425.00",
        "weight": "0.00668491",
        "shared": false
      },
      {
        "name": "MARYLAND ST ECON DEV CORP AIR CARGO REVENUE",
        "value": "1040054.84",
        "weight": "0.00668253",
        "shared": false
      },
      {
        "name": "Washington Metropolitan Area Transit Authority, Series 2025, RB",
        "value": "1038645.70",
        "weight": "0.00667348",
        "shared": false
      },
      {
        "name": "Maryland Stadium Authority Sports Entertainment Facilities Revenue, Series 2023 A",
        "value": "1034419.30",
        "weight": "0.00664632",
        "shared": false
      },
      {
        "name": "State of Maryland Department of Transportation, Series 2024 A",
        "value": "1032954.50",
        "weight": "0.00663691",
        "shared": false
      },
      {
        "name": "MARYLAND ST HLTH & HGR EDUCTNL MARYLAND HEALTH & HIGHER EDUCATIONAL FACILITIES AU",
        "value": "1031303.10",
        "weight": "0.00662630",
        "shared": false
      },
      {
        "name": "MARYLAND ST HLTH & HGR EDUCTNL FACS AUTH REVENUE",
        "value": "1025953.80",
        "weight": "0.00659193",
        "shared": false
      },
      {
        "name": "Maryland Department of Housing & Community Development, Series 2025 D",
        "value": "1024100.00",
        "weight": "0.00658002",
        "shared": false
      },
      {
        "name": "State of Maryland Department of Transportation, Series 2024 A",
        "value": "1023701.30",
        "weight": "0.00657746",
        "shared": false
      },
      {
        "name": "MARYLAND ST STA 4% 6/1/2036",
        "value": "1022381.10",
        "weight": "0.00656898",
        "shared": false
      },
      {
        "name": "Montgomery County Housing Opportunities Commission, Series 2025A",
        "value": "1021211.30",
        "weight": "0.00656146",
        "shared": false
      }
    ]
  },
  "error": null,
  "sources": [
    {
      "label": "N-PORT (fund A)",
      "accession_no": "0002071691-26-011424",
      "as_of": "2026-03-31",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/751656/000207169126011424/0002071691-26-011424-index.htm"
    },
    {
      "label": "N-PORT (fund B)",
      "accession_no": "0002071691-26-011429",
      "as_of": "2026-03-31",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/751656/000207169126011429/0002071691-26-011429-index.htm"
    }
  ]
}