Data / Rankings / Population / Counties in Massachusetts

Counties in Massachusetts by population, 2025

Middlesex County had the highest population of 14 counties in 2025, at 1.67 million. Nantucket County had the lowest, at 14,758. The median was 505,584 and the figure for Massachusetts was 7.15 million. Source: the U.S. Census Bureau.

Highest1,669,979Middlesex County
Lowest14,758Nantucket County
Median505,58414 counties
Massachusetts7,154,084History

All counties, 2025

CSVChart (SVG)

Middlesex CountyMiddlesex County: 1,669,979 persons1,669,979Worcester CountyWorcester County: 888,502 persons888,502Essex CountyEssex County: 826,653 persons826,653Suffolk CountySuffolk County: 791,891 persons791,891Norfolk CountyNorfolk County: 739,749 persons739,749Bristol CountyBristol County: 593,640 persons593,640Plymouth CountyPlymouth County: 546,829 persons546,829Hampden CountyHampden County: 464,338 persons464,338Barnstable CountyBarnstable County: 233,539 persons233,539Hampshire CountyHampshire County: 164,065 persons164,065Berkshire CountyBerkshire County: 128,224 persons128,224Franklin CountyFranklin County: 70,698 persons70,698Dukes CountyDukes County: 21,219 persons21,219Nantucket CountyNantucket County: 14,758 persons14,758
persons. Source: U.S. Census Bureau. Retrieved 2026-10-08.

Full ranking

RankCounties2025
persons		Change on 2024
1Middlesex County1,669,979+0.4%
2Worcester County888,502+0.5%
3Essex County826,653+0.1%
4Suffolk County791,891-0.2%
5Norfolk County739,749+0.3%
6Bristol County593,640+0.5%
7Plymouth County546,829+0.4%
8Hampden County464,338+0.2%
9Barnstable County233,539-0.2%
10Hampshire County164,065-0.4%
11Berkshire County128,224-0.6%
12Franklin County70,698-0.3%
13Dukes County21,219-0.6%
14Nantucket County14,758+0.3%

Other periods

About this ranking

Resident population. Spain and the EU: 1 January, with Spanish figures from the official municipal register (Padrón). United States: Census Bureau population estimates for 1 July. Other countries and the World: World Bank mid-year estimates, which count all residents regardless of legal status or citizenship.

For Denmark, Statistics Denmark counts the registered resident population on 1 January. Greenland and the Faroe Islands are excluded. The annual series selects the first-quarter reference date from FOLK1A. The World Bank series exists for every country, so use it (through compare) to rank countries on one basis.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-08.

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Questions

Which county has the highest population?

Middlesex County, with 1.67 million in 2025, according to the U.S. Census Bureau.

Which county has the lowest population?

Nantucket County, with 14,758 in 2025.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). Retrieved 2026-10-08.

Population: other rankings

Counties in Massachusetts: more rankings