{
  "page": "compare",
  "query": {
    "a": "MPMSX",
    "b": "MFSSX"
  },
  "retrieved_at": "2026-07-07T19:08:00+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 Mississippi Municipal Bond Fund",
    "ticker": "MPMSX",
    "slug": "MPMSX",
    "series_id": "S000002535",
    "html_url": "https://fundwatcher.app/funds/MPMSX/"
  },
  "fund_b": {
    "name": "MFS Massachusetts Municipal Bond Fund",
    "ticker": "MFSSX",
    "slug": "MFSSX",
    "series_id": "S000002534",
    "html_url": "https://fundwatcher.app/funds/MFSSX/"
  },
  "overlap": {
    "coverage_a_by_b": "0.08755661579134256517196603998",
    "coverage_b_by_a": "0.08755661579134256517196603998",
    "shared_count": 45,
    "as_of": {
      "a": "2026-03-31",
      "b": "2026-03-31"
    },
    "a_top": [
      {
        "name": "Jackson County Utility Authority",
        "value": "2000631.40",
        "weight": "0.03277370",
        "shared": false
      },
      {
        "name": "Mississippi Home Corp., Series 2024A",
        "value": "1688631.00",
        "weight": "0.02766261",
        "shared": false
      },
      {
        "name": "Mississippi Development Bank",
        "value": "1325279.25",
        "weight": "0.02171030",
        "shared": false
      },
      {
        "name": "MS MDCEDU 5 06/01/2042",
        "value": "1261411.13",
        "weight": "0.02066403",
        "shared": false
      },
      {
        "name": "Medical Center Educational Building Corp.",
        "value": "1254090.13",
        "weight": "0.02054410",
        "shared": false
      },
      {
        "name": "MS DEV BK 5.25% 1/1/2034",
        "value": "1110241.00",
        "weight": "0.01818761",
        "shared": false
      },
      {
        "name": "W RANKIN UTIL AUTH",
        "value": "1042610.40",
        "weight": "0.01707971",
        "shared": false
      },
      {
        "name": "Mississippi Development Bank, Series 2025",
        "value": "1037956.10",
        "weight": "0.01700346",
        "shared": false
      },
      {
        "name": "Mississippi Development Bank",
        "value": "1034851.30",
        "weight": "0.01695260",
        "shared": false
      },
      {
        "name": "Mississippi Development Bank",
        "value": "1034582.33",
        "weight": "0.01694819",
        "shared": false
      },
      {
        "name": "PUERTO RICO SALES TAX FING COR REGD OID B/E 5.00000000",
        "value": "1032402.75",
        "weight": "0.01691249",
        "shared": true
      },
      {
        "name": "Mississippi Development Bank, Series 2024",
        "value": "1021683.20",
        "weight": "0.01673688",
        "shared": false
      },
      {
        "name": "State of Mississippi, Series 2024",
        "value": "1020528.20",
        "weight": "0.01671796",
        "shared": false
      },
      {
        "name": "State of Mississippi, Series 2018A",
        "value": "1014675.70",
        "weight": "0.01662209",
        "shared": false
      },
      {
        "name": "Mississippi Development Bank",
        "value": "1006948.90",
        "weight": "0.01649551",
        "shared": false
      },
      {
        "name": "MS MSSDEV 5 07/01/2048",
        "value": "1003922.30",
        "weight": "0.01644593",
        "shared": false
      },
      {
        "name": "MISSISSIPPI ST HOME CORP SF MTGE REVENUE",
        "value": "989126.70",
        "weight": "0.01620355",
        "shared": false
      },
      {
        "name": "Mississippi Development Bank",
        "value": "972746.80",
        "weight": "0.01593522",
        "shared": false
      },
      {
        "name": "Mississippi Home Corp.",
        "value": "955213.90",
        "weight": "0.01564801",
        "shared": false
      },
      {
        "name": "MS HOSP 4% 1/1/2040",
        "value": "954595.70",
        "weight": "0.01563788",
        "shared": false
      },
      {
        "name": "Medical Center Educational Building Corp., Series 2017, Ref. RB",
        "value": "913079.10",
        "weight": "0.01495777",
        "shared": false
      },
      {
        "name": "MS MSSSFH 4.05 12/01/2047",
        "value": "909184.20",
        "weight": "0.01489396",
        "shared": false
      },
      {
        "name": "Medical Center Educational Building Corp., Series 2023, RB",
        "value": "889611.30",
        "weight": "0.01457333",
        "shared": false
      },
      {
        "name": "Mississippi Home Corp.",
        "value": "822064.50",
        "weight": "0.01346680",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST BAY TRANSPRTN AUTH SALES TAX REVENUE",
        "value": "815068.05",
        "weight": "0.01335218",
        "shared": true
      },
      {
        "name": "Warren County, Mississippi, Certificates of Participation, Lease Purchase Jail Project Series 2023",
        "value": "806926.35",
        "weight": "0.01321881",
        "shared": false
      },
      {
        "name": "Warren County, Mississippi, Certificates of Participation, Lease Purchase Jail Project Series 2023",
        "value": "797703.15",
        "weight": "0.01306772",
        "shared": false
      },
      {
        "name": "Mississippi Development Bank, Series 2024",
        "value": "765382.50",
        "weight": "0.01253825",
        "shared": false
      },
      {
        "name": "MS DEV BK SPL/AGM 6.88% 12/1/40",
        "value": "763027.50",
        "weight": "0.01249967",
        "shared": false
      },
      {
        "name": "MS UNIV EDU CORP-A",
        "value": "761849.03",
        "weight": "0.01248037",
        "shared": false
      },
      {
        "name": "MS ST HOME SF 4.8% 12/1/45",
        "value": "754596.08",
        "weight": "0.01236155",
        "shared": false
      },
      {
        "name": "MISSISSIPPI ST HOME CORP SF MT REGD B/E GNMA/FN 4.80000000",
        "value": "749706.98",
        "weight": "0.01228146",
        "shared": false
      },
      {
        "name": "San Diego Unified School District, Series 2010C",
        "value": "747424.99",
        "weight": "0.01224408",
        "shared": false
      },
      {
        "name": "Mississippi Home Corp., Series 2024 C",
        "value": "747109.80",
        "weight": "0.01223891",
        "shared": false
      },
      {
        "name": "Mississippi Home Corp., Series 2024 E",
        "value": "742496.25",
        "weight": "0.01216333",
        "shared": false
      },
      {
        "name": "MS MHSG 4.55% 4/1/2042",
        "value": "736179.50",
        "weight": "0.01205986",
        "shared": false
      },
      {
        "name": "MS MSSDEV 4 06/01/2044",
        "value": "719826.08",
        "weight": "0.01179196",
        "shared": false
      },
      {
        "name": "State of Mississippi",
        "value": "714285.34",
        "weight": "0.01170119",
        "shared": false
      },
      {
        "name": "Mississippi Development Bank",
        "value": "700880.10",
        "weight": "0.01148159",
        "shared": false
      },
      {
        "name": "State of Mississippi, Series 2024",
        "value": "698163.60",
        "weight": "0.01143709",
        "shared": false
      },
      {
        "name": "Mississippi State University Educational Building Corp., Series 2024A",
        "value": "662858.63",
        "weight": "0.01085874",
        "shared": false
      },
      {
        "name": "S E ENERGY COOP DT",
        "value": "602226.63",
        "weight": "0.00986548",
        "shared": true
      },
      {
        "name": "University of Mississippi Educational Building Corp., Series 2017 , Ref. RB",
        "value": "583536.60",
        "weight": "0.00955931",
        "shared": false
      },
      {
        "name": "Mississippi Home Corp., Series 2026A",
        "value": "527590.00",
        "weight": "0.00864281",
        "shared": false
      },
      {
        "name": "MFS Institutional Money Market Portfolio, Class A",
        "value": "526050.32",
        "weight": "0.00861759",
        "shared": true
      },
      {
        "name": "Little Rock School District",
        "value": "524720.56",
        "weight": "0.00859580",
        "shared": false
      },
      {
        "name": "Mississippi Development Bank, Series 2025",
        "value": "523145.20",
        "weight": "0.00857000",
        "shared": false
      },
      {
        "name": "WARREN CO-A-REF-REMK",
        "value": "515369.10",
        "weight": "0.00844261",
        "shared": false
      },
      {
        "name": "Mississippi Development Bank, Special Obligation Bonds, Lamar County School District Series 2025",
        "value": "511065.05",
        "weight": "0.00837210",
        "shared": false
      },
      {
        "name": "Mississippi Development Bank, Series 2025",
        "value": "511065.05",
        "weight": "0.00837210",
        "shared": false
      }
    ],
    "b_top": [
      {
        "name": "MFS Institutional Money Market Portfolio, Class A",
        "value": "6780076.38",
        "weight": "0.01677377",
        "shared": true
      },
      {
        "name": "MASSACHUSETTS ST DEV FIN AGY R REGD B/E 5.00000000",
        "value": "5519077.50",
        "weight": "0.01365409",
        "shared": false
      },
      {
        "name": "Commonwealth of Massachusetts Transportation Fund, Series 2025A",
        "value": "5246705.50",
        "weight": "0.01298024",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST DEV FIN AGY REVENUE",
        "value": "5015128.50",
        "weight": "0.01240733",
        "shared": false
      },
      {
        "name": "MA CLEAN WTR TRUST-27",
        "value": "4238510.00",
        "weight": "0.01048599",
        "shared": false
      },
      {
        "name": "MBTA SLS TAX 5.25% 7/1/55",
        "value": "4197145.60",
        "weight": "0.01038365",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST",
        "value": "4174933.60",
        "weight": "0.01032870",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST SCH BLDG AUTH SALES TAX REVENUE",
        "value": "4156830.40",
        "weight": "0.01028392",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST SCH BLDG AUTH SALES TAX REVENUE",
        "value": "4139378.40",
        "weight": "0.01024074",
        "shared": false
      },
      {
        "name": "MA ST TRANS REV 5% 6/1/2053",
        "value": "4128929.20",
        "weight": "0.01021489",
        "shared": false
      },
      {
        "name": "Tri-County Regional Vocational Technical School District, Series CHAPTER 70B",
        "value": "3897596.00",
        "weight": "0.00964257",
        "shared": false
      },
      {
        "name": "MASS DEVEL FIN 4% 10/1/2045",
        "value": "3683306.52",
        "weight": "0.00911243",
        "shared": false
      },
      {
        "name": "PUERTO RICO SALES TAX FING COR REGD OID B/E 5.00000000",
        "value": "3618162.86",
        "weight": "0.00895126",
        "shared": true
      },
      {
        "name": "MASSACHUSETTS ST DEV FIN AGY REVENUE",
        "value": "3613758.75",
        "weight": "0.00894037",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST PORT AUTH",
        "value": "3600171.84",
        "weight": "0.00890675",
        "shared": false
      },
      {
        "name": "Massachusetts Development Finance Agency, Series 2025W",
        "value": "3580581.24",
        "weight": "0.00885829",
        "shared": false
      },
      {
        "name": "Town of Tisbury",
        "value": "3576179.50",
        "weight": "0.00884740",
        "shared": false
      },
      {
        "name": "Massachusetts Housing Finance Agency",
        "value": "3515743.88",
        "weight": "0.00869788",
        "shared": false
      },
      {
        "name": "Massachusetts Bay Transportation Authority, Series 2025 B",
        "value": "3220527.00",
        "weight": "0.00796752",
        "shared": false
      },
      {
        "name": "Massachusetts Educational Financing Authority",
        "value": "3190051.60",
        "weight": "0.00789212",
        "shared": false
      },
      {
        "name": "WAKEFIELD MA REGD B/E 5.00000000",
        "value": "3159303.90",
        "weight": "0.00781605",
        "shared": false
      },
      {
        "name": "Massachusetts Development Finance Agency",
        "value": "3136652.54",
        "weight": "0.00776002",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST DEV FIN AGY REVENUE",
        "value": "3128461.80",
        "weight": "0.00773975",
        "shared": false
      },
      {
        "name": "MA ST TRANS REV 5% 6/1/2049",
        "value": "3112573.20",
        "weight": "0.00770044",
        "shared": false
      },
      {
        "name": "MASS DEVEL FIN 5% 7/1/2048",
        "value": "3106466.46",
        "weight": "0.00768534",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST PORT AUTH REGD B/E AMT 5.00000000",
        "value": "3065727.02",
        "weight": "0.00758455",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST",
        "value": "3061399.50",
        "weight": "0.00757384",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST PORT AUTH",
        "value": "3053706.60",
        "weight": "0.00755481",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST TRANSPRTN FUND REVENUE",
        "value": "3051318.00",
        "weight": "0.00754890",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST DEV FIN AGY R REGD B/E 5.50000000",
        "value": "3048717.60",
        "weight": "0.00754247",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST DEV FIN AGY R REGD B/E 5.00000000",
        "value": "3037816.50",
        "weight": "0.00751550",
        "shared": false
      },
      {
        "name": "Massachusetts Housing Finance Agency",
        "value": "3031967.70",
        "weight": "0.00750103",
        "shared": false
      },
      {
        "name": "Massachusetts Port Authority, Revenue Bonds, Refunding Series 2017A",
        "value": "3019395.90",
        "weight": "0.00746992",
        "shared": false
      },
      {
        "name": "Massachusetts (Commonwealth of), Series 2024 E, GO Bonds",
        "value": "3013826.13",
        "weight": "0.00745615",
        "shared": false
      },
      {
        "name": "Massachusetts Housing Finance Agency, Series 2013B",
        "value": "3000481.50",
        "weight": "0.00742313",
        "shared": false
      },
      {
        "name": "Massachusetts Housing Finance Agency, Series 249",
        "value": "2982815.10",
        "weight": "0.00737942",
        "shared": false
      },
      {
        "name": "S E ENERGY COOP DT",
        "value": "2925100.78",
        "weight": "0.00723664",
        "shared": true
      },
      {
        "name": "MA ST DEV FIN -J2",
        "value": "2888537.40",
        "weight": "0.00714618",
        "shared": false
      },
      {
        "name": "Nashoba Regional School District",
        "value": "2882022.33",
        "weight": "0.00713007",
        "shared": false
      },
      {
        "name": "Commonwealth of Massachusetts Transportation Fund Revenue",
        "value": "2859262.50",
        "weight": "0.00707376",
        "shared": false
      },
      {
        "name": "Massachusetts Development Finance Agency 4.00% 07/01/2039",
        "value": "2848928.03",
        "weight": "0.00704819",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST PORT AUTH",
        "value": "2832906.44",
        "weight": "0.00700855",
        "shared": false
      },
      {
        "name": "Town of Hingham, Series 2025",
        "value": "2813363.75",
        "weight": "0.00696021",
        "shared": false
      },
      {
        "name": "NEW BEDFORD MA",
        "value": "2771977.80",
        "weight": "0.00685782",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST DEV FIN AGY REVENUE",
        "value": "2770168.63",
        "weight": "0.00685334",
        "shared": false
      },
      {
        "name": "MASSACHUSETTS ST DEV FIN AGY REVENUE",
        "value": "2721192.71",
        "weight": "0.00673218",
        "shared": false
      },
      {
        "name": "MA ST DEV FIN AGY-N",
        "value": "2709922.68",
        "weight": "0.00670429",
        "shared": false
      },
      {
        "name": "Massachusetts Housing Finance Agency, Single Family Housing Revenue Bonds, Social Series 2024-234",
        "value": "2705206.90",
        "weight": "0.00669263",
        "shared": false
      },
      {
        "name": "Massachusetts Development Finance Agency",
        "value": "2624785.64",
        "weight": "0.00649367",
        "shared": false
      },
      {
        "name": "CALIFORNIA ST HLTH FACS FING AUTH REVENUE",
        "value": "2485529.50",
        "weight": "0.00614915",
        "shared": false
      }
    ]
  },
  "error": null,
  "sources": [
    {
      "label": "N-PORT (fund A)",
      "accession_no": "0002071691-26-011431",
      "as_of": "2026-03-31",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/751656/000207169126011431/0002071691-26-011431-index.htm"
    },
    {
      "label": "N-PORT (fund B)",
      "accession_no": "0002071691-26-011422",
      "as_of": "2026-03-31",
      "edgar_url": "https://www.sec.gov/Archives/edgar/data/751656/000207169126011422/0002071691-26-011422-index.htm"
    }
  ]
}