Plymouth County's 2026 population is estimated at 550,656, reflecting a 0.78% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Plymouth County is the 7th largest county in Massachusetts. The 2010 population was 495,937 and has grown 11.03% since 2010.
Data after 2023 is projected based on recent change
Overall: 43 years
Female: 44.5 years
Male: 41.7 years
There are 424,239 adults, (105,740 of whom are seniors) in Plymouth County.
Female: 273,288 (51.1%)
Male: 261,787 (48.9%)
The racial composition of Plymouth County includes 76.96% White, 8.02% Black or African American, 4.43% other race, and smaller percentages for Asian, Native American, Native Hawaiian or Pacific Islander and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 411,816 | 76.96% |
| Two or more races | 46,631 | 8.71% |
| Black or African American | 42,910 | 8.02% |
| Other race | 23,723 | 4.43% |
| Asian | 8,987 | 1.68% |
| Native American | 801 | 0.15% |
| Native Hawaiian or Pacific Islander | 207 | 0.04% |
Plymouth County 's average per capita income is $67,303. Household income levels show a median of $114,201. The poverty rate stands at 7.1%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $159,906 | $203,547 |
| Families | $138,892 | $178,644 |
| Households | $114,201 | $151,136 |
| Non Families | $56,912 | $79,447 |
Average Income
Median Household Income
Poverty Rate