By the Numbers
Who Lives in Gardner
Gardner by the Numbers
Sources: US Census Bureau (data.census.gov).
Numbers describe a city, but they also decide things. Population sets how many state representatives the region gets and how much state aid arrives. Household income and home values move what the schools can spend. Every figure on this page comes from the US Census Bureau or the Secretary of the Commonwealth.
People
- Population: 21,287 at the 2020 Census, with a more recent estimate of 21,075.
- Density: about 965 people per square mile across 22.1 square miles of land.
- Under 18: 18.3 percent. Under 5: 5.2 percent.
- 65 and over: 19.3 percent.
- Households: 8,940, averaging 2.2 people.
- Veterans: 7.0 percent of adults.
Race, Ethnicity and Origin
- White alone: 81.3 percent, and 79.8 percent white and not Hispanic or Latino.
- Black or African American alone: 4.7 percent.
- Asian alone: 2.8 percent.
- American Indian and Alaska Native alone: 0.2 percent.
- Two or more races: 10.7 percent.
- Hispanic or Latino, of any race: 9.4 percent.
- Born outside the United States: 8.0 percent.
- Speak a language other than English at home: 13.9 percent.
Work, Money and Housing
- Median household income: $67,518.
- In the labor force: 58.8 percent of residents 16 and over.
- Living below the poverty line: 14.3 percent.
- Median home value: $301,600.
- Median gross rent: $1,109 a month.
- Owner occupied homes: 56.7 percent, so a little over four in ten households rent.
Who Votes, and How They Register
Gardner had 16,067 registered voters as of August 22, 2026, and the striking number is how few of them belong to a party.
- Unenrolled: 11,937 voters, 74.30 percent.
- Democratic: 2,508 voters, 15.61 percent.
- Republican: 1,417 voters, 8.82 percent.
- Political designations: 205 voters, 1.28 percent.
An unenrolled voter in Massachusetts can take either party’s ballot at a primary and stay unenrolled afterward. With nearly three quarters of Gardner voters unenrolled, that bloc is the one every candidate has to persuade, and it is open to anyone who registers.
At the city election of November 4, 2025, 3,844 of 15,537 registered voters cast a ballot, which the City Clerk’s certified results put at 24.74 percent. That one election chose the Mayor, all eleven councillors and three School Committee seats. Roughly one registered voter in four made every one of those choices for the whole city, which tells you exactly what a single ballot is worth in a Gardner election.