Hillsborough County, New Hampshire

Hillsborough County population, land area and income

Hillsborough County had 430,462 residents in the Census Vintage 2024 estimate, on 876.5 square miles of land. It is the most populous of New Hampshire's 10 county-equivalents. That works out to 491.1 people per square mile, 5.1 times the US average of 96.3, and in the top tenth nationally.

The median county-equivalent in New Hampshire has 85,562 residents, so Hillsborough County is 5.0 times that size.

Its SAIPE 2023 median household income of $103,181 is in the top tenth among 3,143 counties with an estimate.

How Hillsborough County's population changed since 2020

Hillsborough County gained 7,533 residents between the July 2020 and July 2024 estimates, a rise of 1.8%. That ranks 9th of 10 in New Hampshire for growth. The median New Hampshire county changed by +2.3%, and the state as a whole by +2.2%.

Since the April 2020 estimates base, Hillsborough County recorded 17,628 births and 16,832 deaths, a natural change of +796. Net international migration added +6,554 and net domestic migration, people moving to or from other US counties, came to -74. The largest single component was international migration, which added 6,554 people.

Where Hillsborough County is

The Census internal point of Hillsborough County is at 42.911500, -71.723100. It sits in UTM zone 19N. The map shades New Hampshire's 10 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Hillsborough County outlined. Dots are towns of 1,000+ people with residents in it.

Towns in Hillsborough County

2 incorporated places of 1,000+ people have residents in Hillsborough County, 208,237 people together, or 48% of the county. Each figure counts only the part of the town inside Hillsborough County; towns marked "part" extend into another county. The largest is Manchester with 116,386.

Counties bordering Hillsborough County

The Census 2024 county adjacency file lists 7 neighbors for Hillsborough County, including 3 across a state line. The most populous is Middlesex County, MA, with 1,668,956 residents. Distances run between Census internal points in a straight line.

• MA

  Middlesex County, MA

  1,668,956 people

  34 mi SSE

• MA

  Worcester County, MA

  881,248 people

  43 mi SSW

• MA

  Essex County, MA

  823,938 people

  47 mi ESE

• Rockingham County

  322,433 people

  32 mi E

• Merrimack County

  157,869 people

  27 mi N

• Cheshire County

  78,078 people

  27 mi W

• Sullivan County

  44,012 people

  40 mi NW

Distance to Concord and the nearest big city

Concord is 22.5 miles NNE of Hillsborough County's internal point in a straight line. The nearest place of 100,000 or more is Manchester, NH (population 116,386), 15.0 miles away.

Hillsborough County FIPS code

The FIPS code of Hillsborough County is 33011: state code 33 for New Hampshire plus county code 011. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $103,181.