Plymouth County, Massachusetts

Plymouth County population, land area and income

Plymouth County had 542,090 residents in the Census Vintage 2024 estimate, on 658.5 square miles of land. It ranks 7th of 14 in Massachusetts by population and 5th by land area. That works out to 823.2 people per square mile, 8.6 times the US average of 96.3, and in the top tenth nationally.

The median county-equivalent in Massachusetts has 503,121 residents, about the same as Plymouth County.

Its SAIPE 2023 median household income of $107,828 is in the top tenth among 3,143 counties with an estimate.

How Plymouth County's population changed since 2020

Plymouth County gained 13,636 residents between the July 2020 and July 2024 estimates, a rise of 2.6%. That ranks 4th of 14 in Massachusetts for growth. The median Massachusetts county changed by +2.2%, and the state as a whole by +2.0%.

Since the April 2020 estimates base, Plymouth County recorded 22,428 births and 23,180 deaths, a natural change of -752. Net international migration added +9,677 and net domestic migration, people moving to or from other US counties, came to +2,824. The largest single component was international migration, which added 9,677 people.

Where Plymouth County is

The Census internal point of Plymouth County is at 41.987200, -70.741900. It sits in UTM zone 19N. The map shades Massachusetts's 14 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Plymouth County outlined. Dots are towns of 1,000+ people with residents in it.

Towns in Plymouth County

2 incorporated places of 1,000+ people have residents in Plymouth County, 134,955 people together, or 25% of the county. Each figure counts only the part of the town inside Plymouth County; towns marked "part" extend into another county. The largest is Brockton with 105,788.

Counties bordering Plymouth County

The Census 2024 county adjacency file lists 4 neighbors for Plymouth County. The most populous is Suffolk County, MA, with 793,144 residents. Distances run between Census internal points in a straight line.

• Suffolk County

  793,144 people

  28 mi NNW

• Norfolk County

  740,754 people

  26 mi WNW

• Bristol County

  588,593 people

  24 mi SW

• Barnstable County

  232,570 people

  35 mi ESE

Distance to Boston and the nearest big city

Boston is 30.5 miles NNW of Plymouth County's internal point in a straight line. The nearest place of 100,000 or more is Brockton, MA (population 105,788), 15.9 miles away. The nearest place of 10,000 or more is Bridgewater Town, MA (population 29,167), 12.2 miles away.

Plymouth County FIPS code

The FIPS code of Plymouth County is 25023: state code 25 for Massachusetts plus county code 023. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $107,828.