Counties · Massachusetts

Counties of Massachusetts

Massachusetts has 14 counties. Middlesex County is the largest with 1,669,979 residents in 2025. 10 of the 14 gained residents between 2020 and 2025 by the Census Bureau's estimates.

What counties are in Massachusetts?

Sorted by the 2025 population estimate; sort by any column.

Counties of Massachusetts: 2025 estimate, change since 2020, ACS 2020-2024 5-year estimates

Middlesex County	1,669,979	+2.3%	68	357	$130,847	$727,800
Worcester County	888,502	+3.1%	90	191	$95,939	$423,700
Essex County	826,653	+2.1%	42	174	$101,883	$619,100
Suffolk County	791,891	−1.1%	4	235	$95,631	$705,800
Norfolk County	739,749	+1.9%	35	154	$130,739	$683,900
Bristol County	593,640	+2.5%	29	131	$85,625	$451,200
Plymouth County	546,829	+3.0%	52	111	$114,201	$556,000
Hampden County	464,338	−0.3%	29	104	$71,306	$298,800
Barnstable County	233,539	+2.0%	54	57	$95,241	$629,000
Hampshire County	164,065	+1.1%	25	35	$87,001	$390,300
Berkshire County	128,224	−0.6%	40	40	$76,013	$305,400
Franklin County	70,698	−0.5%	33	19	$74,907	$329,000
Dukes County	21,219	+3.0%	10	5	$125,786	$1,165,800
Nantucket County	14,758	+3.6%	4	7	$139,688	$1,593,800

Source: PEP Vintage 2025 (CO-EST2025); American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) · Census population estimates

How these figures are made: methodology and release checks · reading a margin of error · every state · corrections