Massachusetts County Map
Labeled county boundary map and complete directory of all 14 counties in Massachusetts (MA, State FIPS 25). View 5-digit FIPS codes, county seats, land area in square miles, and official county government websites below.
Showing all 14 counties in Massachusetts. Use the search box below to filter by county name, 5-digit FIPS code, or county seat.
Massachusetts County Statistics & Summary
Total Counties
14
Largest by Land Area
Worcester County
Smallest by Land Area
Nantucket County
All 14 Counties in Massachusetts (FIPS, County Seat & Official Website)
| County Name | 5-Digit FIPS | Seat / Administrative Center | Land Area (sq mi) | Coordinates | Official Website |
|---|---|---|---|---|---|
| Barnstable County | 25001 | Barnstable | 394.2 | 41.706°, -70.165° | Official Site |
| Berkshire County | 25003 | Pittsfield | 926.9 | 42.371°, -73.218° | — |
| Bristol County | 25005 | Taunton | 553.1 | 41.749°, -71.089° | Official Site |
| Dukes County | 25007 | Edgartown | 103.2 | 41.381°, -70.701° | Official Site |
| Essex County | 25009 | Salem | 492.5 | 42.643°, -70.865° | — |
| Franklin County | 25011 | Greenfield | 699.2 | 42.584°, -72.592° | Official Site |
| Hampden County | 25013 | Springfield | 617 | 42.136°, -72.636° | Official Site |
| Hampshire County | 25015 | Northampton | 527.2 | 42.340°, -72.664° | Official Site |
| Middlesex County | 25017 | Cambridge | 817.9 | 42.482°, -71.395° | — |
| Nantucket County | 25019 | Nantucket | 46.2 | 41.293°, -70.102° | Official Site |
| Norfolk County | 25021 | Dedham | 396.1 | 42.172°, -71.181° | Official Site |
| Plymouth County | 25023 | Plymouth | 658.5 | 41.987°, -70.742° | Official Site |
| Suffolk County | 25025 | Boston | 58.3 | 42.333°, -71.013° | — |
| Worcester County | 25027 | Worcester | 1,510.7 | 42.312°, -71.940° | — |
How Massachusetts Counties and 5-Digit FIPS Codes Work
In U.S. Census Bureau TIGER/Line geography, Massachusetts (MA) is assigned the 2-digit state Federal Information Processing Series (FIPS) code 25 and covers 7,801 square miles of land area across 14 counties in the Eastern Time (ET) zone (with Boston as the state capital). Every county in the directory above carries a unique 5-digit GEOID formed by combining state prefix 25 with a 3-digit county code (ranging alphabetically from Barnstable County at 25001 to Worcester County at 25027).
Because U.S. Postal Service 5-digit ZIP Codes follow mail carrier delivery routes rather than local government borders, many postal addresses in Massachusetts carry a neighboring city’s mailing name or sit inside a multi-county ZIP Code Tabulation Area (ZCTA). Property tax assessments, deed recording, circuit and county court venue, voter registration precincts, sheriff jurisdiction, and county sales tax rates in Massachusetts are determined by the legal county boundary shown on the map above rather than the postal city name on an envelope.
Land area figures in square miles and internal centroid coordinates (INTPTLAT, INTPTLON) come directly from the U.S. Census Bureau’s current TIGERweb State_County benchmark, while 14 administrative seats and 9 verified official government websites are cross-referenced from Wikidata (CC0). Need a clean outline worksheet without county labels, or want to verify which Massachusetts county a specific home or business address sits in? Open the Blank Map of Massachusetts, run a street-segment check on Address to County Lookup, check multi-county postal overlap on ZIP Code to County Lookup, or browse all 50 states on the National U.S. County Map.
Adjacent State County Maps
Explore county maps and FIPS directories for states bordering Massachusetts: