Massachusetts Counties, Demographics & Geography
Complete official guide to all 14 counties in Massachusetts (MA). Explore 2024 US Census population estimates, county seats, FIPS codes, land areas, and interactive mapping tools powered by GeoMap Suite.
Massachusetts County Breakdown
Showing 9 of 9 documented counties and seats.
County Name | FIPS | County Seat | Population (Census) | Land Area | Quick Tool |
|---|---|---|---|---|---|
| Middlesex County | 25017 | Cambridge / Lowell | 1,632,002 | 824 sq mi | Lookup |
| Worcester County | 25027 | Worcester | 862,111 | 1,511 sq mi | Lookup |
| Essex County | 25009 | Salem / Lawrence | 809,829 | 498 sq mi | Lookup |
| Suffolk County (Boston) | 25025 | Boston | 797,936 | 58 sq mi | Lookup |
| Norfolk County | 25021 | Dedham | 725,981 | 396 sq mi | Lookup |
| Bristol County | 25005 | Taunton / New Bedford | 579,200 | 553 sq mi | Lookup |
| Plymouth County | 25023 | Plymouth / Brockton | 530,819 | 659 sq mi | Lookup |
| Hampden County | 25013 | Springfield | 465,825 | 618 sq mi | Lookup |
| Barnstable County (Cape Cod) | 25001 | Barnstable | 228,996 | 394 sq mi | Lookup |
Geographic Structure of Massachusetts Counties
County Administration & Governance
In Massachusetts, county governments manage vital public infrastructure, tax assessments, law enforcement, judicial courts, election administration, and public records. The county seat (Cambridge / Lowell and other municipal headquarters) houses the primary courthouse, commissioners, and sheriff’s department.
All Massachusetts counties carry a unique 5-digit Federal Information Processing Standard (FIPS) code, where the first two digits (25) designate the state and the remaining three digits identify each specific jurisdiction.
Geographic & Demographic Highlights
- Most Populous County:Middlesex County (1,632,002 residents)
- Largest by Land Area:Worcester County (1,511 sq mi)
- State Capital:Boston
- Census Bureau Region:Northeast United States
Demographic calculations derive from the United States Census Bureau 2024 Population Estimates Program (PEP) and TIGER/Line geographic boundary files.