Fastest Growing Counties in New Hampshire (2026)

County
Rank
Change (2020)
2026 Pop.
2020 Pop.
Carroll County15.47%53,00250,251
Rockingham County23.66%326,153314,633
Strafford County33.56%135,755131,084
Hillsborough County43.19%436,388422,902
Merrimack County52.95%158,609154,061
Grafton County62.48%93,45791,193
Cheshire County72.39%78,37076,541
Sullivan County82.15%43,99843,073
Belknap County92.11%65,12563,779
Coos County100.24%31,30931,235

New Hampshire Counties Growth Overview

New Hampshire's counties show varied growth patterns from 2020 to 2026. Carroll County leads with 0.89% annualized growth, followed by Rockingham County (0.6%) and Strafford County (0.59%). The largest counties are Hillsborough County (436,388), Rockingham County (326,153), and Merrimack County (158,609). All 10 counties in New Hampshire are growing. Overall, counties averaged 0.46% annualized growth, with total population growing by 0.52% annually.

Change (2020)

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