RANKING · 2025 ESTIMATES · 10 SHOWN OF 10

Most population lost, New Hampshire counties

New Hampshire counties that lost the most residents from the 2020 census to 2025, by raw count of people rather than percentage. This list covers the 10 counties in New Hampshire that qualify, ranked against each other statewide.

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SAME RANKING BYCities States Metros

YEAR2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION CHANGEVS 2000

01Coos County, NHNH31,343+75−104%

02Sullivan County, NHNH43,961+898−52%

03Belknap County, NHNH65,147+1,442−80%

04Cheshire County, NHNH78,269+1,811−51%

05Grafton County, NHNH93,225+2,107−69%

06Carroll County, NHNH52,784+2,677−68%

07Strafford County, NHNH135,043+4,154−48%

08Merrimack County, NHNH158,078+4,270−74%

09Rockingham County, NHNH324,077+9,901−69%

10Hillsborough County, NHNH433,415+10,478−77%

SHOWING 1–10 OF 10

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UPDATED 2026-07-15 · DATA: US CENSUS BUREAU POPULATION ESTIMATES