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Population Review

Census ACS 2023 · 10 counties

Largest Counties in New Hampshire

New Hampshire has 10 counties with Census data available. The largest is Hillsborough County with a population of 424,732. County-level data is important because counties are the primary unit of local government in most states, responsible for courts, elections, public health, and infrastructure. Population distribution across counties reveals where growth is concentrated and where rural decline may be occurring.

Source: Census ACS 2023 5-Year Estimates

#CountyPopulationMedian Income
1Sullivan County43,529$75,929
2Strafford County131,743$86,564
3Rockingham County317,163$113,927
4Merrimack County155,018$93,944
5Hillsborough County424,732$100,436
6Grafton County91,759$84,021
7Coos County31,386$58,439
8Cheshire County76,945$81,001
9Carroll County51,259$82,961
10Belknap County64,300$87,983

More Rankings for New Hampshire

Frequently Asked Questions

Hillsborough County is the #1 ranked county in New Hampshire by population, with a value of 424,732 according to Census ACS 2023 data.

New Hampshire has 10 counties tracked in Census ACS 2023 data.

All data comes from the American Community Survey (ACS) 2023 5-Year estimates by the US Census Bureau.

Data from the American Community Survey 2023 5-Year estimates. Covers all counties in New Hampshire.