Town · Massachusetts
Ayer, Massachusetts
Ayer, town, in Middlesex County, Massachusetts. Ayer had 9,267 residents on July 1, 2025 by the Census Bureau's estimate, up 9.2% since 2020; the 2020 Census counted 8,479 and the ACS 2020-2024 5-year estimates put it at 8,645 (±27). GEOID 2501703005.
Residents, July 2025 estimate
9,267
Census Bureau estimate (no margin published)
2020 Census count: 8,479 · ACS 2020-2024: 8,645 ±27
Median household income
$101,875
±$14,619 (90% margin)
Massachusetts: $103,960
Median home value
$463,800
±$29,469 (90% margin)
Massachusetts: $562,100
Median gross rent
$1,415
±$180 (90% margin)
Massachusetts: $1,762
Where is Ayer and what county is it in?
Ayer is a town in Middlesex County, Massachusetts. It covers 8.9 square miles of land, 948 residents per square mile in 2020.
One place lies inside Ayer: Ayer (CDP, 2,986 in 2020). Part of Devens (CDP) also lies in it.
Ayer is in the Boston-Cambridge-Newton, MA-NH metropolitan statistical area, which takes in 7 counties (Census Bureau delineation, July 2023).
Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files
How many people live in Ayer, and is it growing?
The Census Bureau estimates that 9,267 people lived in Ayer on July 1, 2025, up 9.2% since 2020, faster than Massachusetts (+1.7%). The 2020 Census counted 8,479 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 8,645 (±27).
| Measure | Ayer | Middlesex County | Change since 2015-2019 |
|---|---|---|---|
| Total population | 8,645±27 | 1,638,365 | +539 |
| Households | 3,654±216 | 634,215 | no clear change |
| Average household size | 2.29±0.14 | 2.49 | no clear change |
| Housing units | 3,891±227 | 664,267 | no clear change |
Ayer's population since 2000
From 7,287 in 2000 to 9,267 in 2025: up 27.2%. The 2000, 2010 and 2020 figures are census counts, each for Ayer as it was drawn that year: a place that annexed land, or a community that has since incorporated, covered a different area then. The 2005 figure is the Census Bureau's intercensal estimate, revised to fit the 2000 and 2010 counts and drawn on 2010 boundaries; 2015 and 2025 are July 1 estimates made from the census before them.
Source: The 2000, 2010 and 2020 Census counts and the Census Bureau's population estimates (intercensal 2000-2010, Vintage 2020, Vintage 2025) · Census population estimates
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); Census PEP Vintage 2025 (SUB-EST2025, CO-EST2025); 2020 Census P.L. 94-171 · Check it at data.census.gov
Who lives in Ayer?
The median resident of Ayer is 39.2 years old; 20.3% are under 18 and 14.5% are 65 or older. The largest group is non-Hispanic white residents at 69.3%, then Hispanic or Latino residents (of any race) at 14.9%. 10.0% of residents were born outside the United States.
| Measure | Ayer | Middlesex County | Change since 2015-2019 |
|---|---|---|---|
| Median age | 39.2±2.8 | 38.9 | no clear change |
| Under 18 years | 20.3%±2.8 pts | 19.5% | – |
| 65 years and over | 14.5%±2.8 pts | 16.3% | – |
| Male | 49.4%±3.1 pts | 49.4% | – |
| Hispanic or Latino (any race) | 14.9%±6.9 pts | 9.3% | +9.2 pts |
| White alone, not Hispanic | 69.3%±7.5 pts | 65.1% | −13.1 pts |
| Black or African American alone, not Hispanic | 5.3%±4.0 pts | 4.7% | – |
| Asian alone, not Hispanic | 5.9%±3.1 pts | 13.6% | no clear change |
| American Indian and Alaska Native alone, not Hispanic | 0.0%±0.5 pts | 0.1% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0%±0.5 pts | 0.0% | – |
| Two or more races, not Hispanic | 4.6%±2.3 pts | 5.8% | – |
| Some other race alone, not Hispanic | 0.0%±0.5 pts | 1.4% | – |
| Born outside the United States | 10.0%±3.8 pts | 23.1% | no clear change |
| Speak a language other than English at home (age 5+) | 14.0%±5.0 pts | 29.1% | – |
| Civilian veterans (age 18+) | 6.8%±2.4 pts | 3.3% | – |
| With a disability | 16.3%±3.2 pts | 9.9% | – |
| No health insurance coverage | 3.7%±1.9 pts | 2.4% | no clear change |
| High school graduate or higher (age 25+) | 91.9%±4.8 pts | 93.2% | – |
| Bachelor's degree or higher (age 25+) | 42.3%±5.6 pts | 59.5% | no clear change |
| Graduate or professional degree (age 25+) | 18.0%±4.4 pts | 30.5% | – |
| Lived in the same house a year earlier | 89.3%±4.3 pts | 87.2% | – |
| Moved from another state in the past year | 1.8%±1.5 pts | 2.7% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profiles DP02, DP05) · Check it at data.census.gov
What do households in Ayer earn?
Half of Ayer's 3,654 households earn less than $101,875 a year (±$14,619), against $130,847 in Middlesex County and $103,960 in Massachusetts. In 2015-2019 it was $114,181 in 2024 dollars; the margins of error cannot tell the two periods apart. 10.7% of residents live below the poverty line.
| Measure | Ayer | Middlesex County | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $101,875±$14,619 | $130,847 | no clear change |
| Mean household income | $137,670±$13,385 | $178,070 | – |
| Per capita income | $58,385±$5,386 | $69,556 | no clear change |
| People below the poverty line | 10.7%±4.5 pts | 7.7% | no clear change |
| Children under 18 below the poverty line | 14.9%±11.9 pts | 7.9% | – |
| Households receiving SNAP | 11.5%±5.0 pts | 9.3% | – |
| Households with a computer | 94.9%±3.9 pts | 97.0% | – |
| Households with a broadband subscription | 90.8%±4.7 pts | 94.7% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What does housing cost in Ayer?
Owners occupy 69.2% of Ayer's occupied homes and renters 30.8%. The median owner-occupied home is valued at $463,800 by its owner (±$29,469). The median renter pays $1,415 a month including utilities, and 20.1% of renters pay 35% or more of their income on rent.
| Measure | Ayer | Middlesex County | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $463,800±$29,469 | $727,800 | +$61,855 |
| Median gross rent | $1,415±$180 | $2,201 | no clear change |
| Renters paying 35% or more of income on rent | 20.1%±8.6 pts | 37.6% | no clear change |
| Median monthly owner costs, with a mortgage | $2,607±$188 | $3,224 | – |
| Owner-occupied homes | 69.2%±5.5 pts | 61.3% | no clear change |
| Renter-occupied homes | 30.8%±5.5 pts | 38.7% | – |
| Housing units | 3,891±227 | 664,267 | no clear change |
| Homeowner vacancy rate | 1.4%±2.0 pts | 0.6% | – |
| Rental vacancy rate | 2.6%±4.2 pts | 3.4% | – |
| Single-family detached homes | 51.1%±6.0 pts | 46.5% | – |
| Mobile homes | 1.1%±0.9 pts | 0.4% | – |
| Built 2020 or later | 0.9%±0.9 pts | 1.2% | – |
| Built 2010 to 2019 | 11.4%±3.5 pts | 7.3% | – |
| Built 1939 or earlier | 20.7%±4.5 pts | 32.3% | – |
| Households with no vehicle | 3.8%±2.0 pts | 10.3% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP04) · Check it at data.census.gov
How many new homes is Ayer building?
Builders took permits for 11 new housing units in Ayer in 2025 (4 in single-family houses), 1.2 per 1,000 residents against 1.7 across Massachusetts.
Counts of units in permits a local office issued; not every permitted unit is built. A year marked with months was reported for part of the year.
Source: Building Permits Survey, annual place files 2019-2025, U.S. Census Bureau · Census Building Permits Survey
How do people in Ayer work and get to work?
70.4% of Ayer's workers drive alone and 21.6% work from home. The average trip to work takes 33.0 minutes.
| Measure | Ayer | Middlesex County | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 74.8%±3.8 pts | 69.9% | – |
| Unemployment rate | 7.0%±4.7 pts | 4.4% | – |
| Drove alone to work | 70.4%±6.0 pts | 54.2% | – |
| Carpooled | 2.9%±1.7 pts | 6.3% | – |
| Public transportation | 3.6%±1.7 pts | 7.2% | – |
| Walked | 0.7%±1.7 pts | 4.2% | – |
| Worked from home | 21.6%±6.0 pts | 24.7% | – |
| Mean travel time to work | 33.0 min±2.9 | 29.9 min | no clear change |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What census tracts are in Ayer?
2 census tracts lie mostly in Ayer (2020 census blocks). Their median household incomes run from $74,973 (Tract 3251.02) to $148,258 (Tract 3251.01).
| Tract | Residents, 2020-2024 | Median household income |
|---|---|---|
| Tract 3251.02Middlesex County | 4,450 | $74,973 |
| Tract 3251.01Middlesex County | 4,195 | $148,258 |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); 2020 block assignment files (tract share = share of the tract's census blocks in Ayer) · Census block assignment files
How does Ayer compare with other places in Massachusetts?
By the Census Bureau's July 2025 estimates, Ayer is the 1,333rd-most populous of the 16,079 U.S. towns and townships that have one and the 111th-most populous of 266 in Massachusetts.
Ayer ranks 276th of 453 places in Massachusetts with 1,000 or more residents and a reliable estimate, by median household income.
| Measure | Rank | Of |
|---|---|---|
| Population, July 2025 estimate | 111th | 266 |
| Growth 2020-2025 (PEP) | 7th | 292 |
| Residents per square mile | 193rd | 461 |
| Median household income | 276th | 453 |
| Per capita income | 199th | 460 |
| Median home value | 281st | 459 |
| Median gross rent | 251st | 410 |
| Poverty rate | 68th | 338 |
| Bachelor's degree or higher | 279th | 459 |
| Median age | 400th | 461 |
| Owner-occupied share | 348th | 460 |
| Work from home | 147th | 429 |
| Travel time to work | 123rd | 459 |
Ayer's figures with every place in Massachusetts (CSV)
Every place in Massachusetts, sortable · Compare Ayer with other places
Source: PlainCities ranks computed from the American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) and PEP Vintage 2025 · How ranks are computed
How reliable are the figures for Ayer?
12 of the 57 figures for Ayer on this page carry a coefficient of variation over 40% and are marked with a ring: they come from a small sample, so read them as rough.
The American Community Survey samples about one household in eight over five years, so every figure is an estimate with a 90% margin of error (shown under each value). A ring marks an estimate whose coefficient of variation is over 40%. A change is called only when the gap between the two periods is larger than their combined 90% margin (the square root of the sum of the two squared margins), the Census Bureau's test. How to read a margin of error.
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026): margins of error as published · ACS technical documentation
How these figures are made: methodology and release checks · reading a margin of error · every state · corrections
Not on this page: crime, weather and schools for Ayer are other agencies' records. Crime: the FBI's Crime Data Explorer · climate: NOAA's U.S. Climate Normals · schools: the National Center for Education Statistics' school search.