How many people live in Plymouth County, MA?
Updated Apr. 6, 2026Refreshed annually
In 2024, there were about 542,100 people living in Plymouth County, MA. That makes Plymouth County the seventh-most populous county in Massachusetts. It is home to 7.6% of people living in the state.
542K
population of Plymouth County, MA (2024)
7.6%
County share of the Massachusetts population (2024)
About 542,100 people lived in Plymouth County, MA in 2024.
Population estimates, 2000–2024
What are Plymouth County, MA’s age demographics?
About 113,100 Plymouth County residents are aged 65 and older in 2024. That represents 20.9% of its population. For comparison, the age group represents 18.7% of Massachusetts’ population and 18% in the US overall.
Another 109,700 Plymouth County residents, or 20.2% of the population, were children under 18. For comparison, the age group represents 19% of Massachusetts’ population and 21.6% in the US overall.
A lower share of Plymouth County, MA's population is aged 25–44 than the US as a whole.
Population estimates by age group, (2024)
What are Plymouth County, MA’s racial and ethnic demographics?
Non-Hispanic white residents make up 78.2% of the Plymouth County, MA population, higher than the national share of 57.5%.
In contrast, Plymouth County’s Hispanic population accounts for 5.3%, below the 20% nationwide, and the non-Hispanic Asian population makes up 1.8% of the county, compared with 6.5% nationally.
Racial and ethnic make up differ based on location. These figures reflect how people identified their race alone (not in combination with other races), and separate out Hispanic or Latino ethnicity, following Census reporting standards.
Plymouth County, MA has a higher share of a non-Hispanic white population than Massachusetts as a whole.
Population estimates by race and ethnicity, (2024)
The largest city or town in Plymouth County, MA is Brockton with about 105,800 residents in 2024.
Cities and towns in Plymouth County, MA ranked by population
Population (2024), includes only portions within county
| City or town | Population | |
|---|---|---|
| 1. | Brockton | 105,788 |
| 2. | Plymouth | 66,663 |
| 3. | Bridgewater Town | 29,167 |
| 4. | Marshfield | 26,043 |
| 5. | Middleborough | 24,847 |
| 6. | Hingham | 24,414 |
| 7. | Wareham | 23,526 |
| 8. | Scituate | 19,598 |
| 9. | Pembroke | 18,428 |
| 10. | Rockland | 17,708 |
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Methodology
USAFacts standardizes data, in areas such as time and demographics, to make it easier to understand and compare.
The analysis was generated with the help of AI and reviewed by USAFacts for accuracy.
Page sources
USAFacts endeavors to share the most up-to-date information available. We sourced the data on this page directly from government agencies; however, the intervals at which agencies publish updated data vary.
