What are the largest counties in Massachusetts?

Middlesex County is the largest county in Massachusetts, with 1,669,979 residents in 2025 (Census PEP). Worcester County (888,502) and Essex County (826,653) come next.

Data as of 2025 · updated November 5, 2026

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All 14 ranked Massachusetts counties

Massachusetts counties ranked by population
Rank	County	Residents 2025	Change 2020–25
1	Middlesex County	1,669,979	+2.8%
2	Worcester County	888,502	+3.7%
3	Essex County	826,653	+2.3%
4	Suffolk County	791,891	+0.1%
5	Norfolk County	739,749	+2.2%
6	Bristol County	593,640	+2.9%
7	Plymouth County	546,829	+3.5%
8	Hampden County	464,338	+0.1%
9	Barnstable County	233,539	+2.4%
10	Hampshire County	164,065	+10.4%
11	Berkshire County	128,224	−1.2%
12	Franklin County	70,698	−0.3%
13	Dukes County	21,219	+3.1%
14	Nantucket County	14,758	+3.6%

How this is ranked

The Census Bureau's July 1 resident population estimates for 2025, largest first, with the change since 2020. Counties with fewer than 1,000 residents are not ranked. Areas without an estimate for the same year as the others are not ranked.

Source: U.S. Census Bureau, Population Estimates Program (Vintage 2025). Figures come from public federal statistics and are informational only, not investment advice. Check the source before relying on a number. Methodology: how ranks and figures are built.

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Questions

What is the largest county in Massachusetts?

Middlesex County is the largest county in Massachusetts, with 1,669,979 residents in 2025 (Census PEP). Worcester County (888,502) and Essex County (826,653) come next.

How is this ranking calculated?

More rankings for Massachusetts

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