Essex County, Massachusetts

county in Massachusetts, United States

Essex County is a county in the northeastern part of the state of Massachusetts. As of the 2020 census, the total population was 809,829.[1] It is the third-most populous county in the state. It is part of the Greater Boston area (the BostonCambridgeNewton, MA–NH Metropolitan Statistical Area).

Essex County
Former Essex County Courthouse in Salem
Former Essex County Courthouse in Salem
Official seal of Essex County
Map of Massachusetts highlighting Essex County
Location within the U.S. state of Massachusetts
Map of the United States highlighting Massachusetts
Massachusetts's location within the U.S.
Coordinates: 42°38′08″N 70°58′15″W / 42.635475°N 70.970825°W / 42.635475; -70.970825
Country United States
State Massachusetts
Named forEssex
SeatSalem and Lawrence
Largest cityLynn
 • Total828 sq mi (2,140 km2)
 • Land493 sq mi (1,280 km2)
 • Water336 sq mi (870 km2)  41%
 • Total809,829
 • Density1,643/sq mi (634/km2)
Time zoneUTC−5 (Eastern)
 • Summer (DST)UTC−4 (EDT)
Congressional districts3rd, 6th

The largest city in Essex County is Lynn. The county was named after the English county of Essex. It has two traditional county seats: Salem and Lawrence.


  1. "QuickFacts: Essex County, Massachusetts". United States Census Bureau. Retrieved January 3, 2024.