Town · Maine
Monmouth, Maine
Monmouth, town, in Kennebec County, Maine. Monmouth had 4,252 residents on July 1, 2025 by the Census Bureau's estimate, up 4.3% since 2020; the 2020 Census counted 4,066 and the ACS 2020-2024 5-year estimates put it at 4,162 (±26). GEOID 2301146405.
Residents, July 2025 estimate
4,252
Census Bureau estimate (no margin published)
2020 Census count: 4,066 · ACS 2020-2024: 4,162 ±26
Median household income
$74,648
±$18,044 (90% margin)
Maine: $74,733
Median home value
$274,100
±$21,353 (90% margin)
Maine: $296,600
Median gross rent
$1,271
±$175 (90% margin)
Maine: $1,139
Where is Monmouth and what county is it in?
Monmouth is a town in Kennebec County, Maine. It covers 34.0 square miles of land, 120 residents per square mile in 2020.
Monmouth is in the Augusta-Waterville, ME micropolitan statistical area (Census Bureau delineation, July 2023).
Monmouth is the same area as Census Tract 130 of Kennebec County: the tract's figures are Monmouth's own.
Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files
How many people live in Monmouth, and is it growing?
The Census Bureau estimates that 4,252 people lived in Monmouth on July 1, 2025, up 4.3% since 2020, faster than Maine (+3.8%). The 2020 Census counted 4,066 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 4,162 (±26).
| Measure | Monmouth | Kennebec County | Change since 2015-2019 |
|---|---|---|---|
| Total population | 4,162±26 | 126,808 | +62 |
| Households | 1,799±177 | 54,312 | no clear change |
| Average household size | 2.30±0.23 | 2.25 | no clear change |
| Housing units | 2,197±206 | 63,521 | no clear change |
Monmouth's population since 2000
From 3,785 in 2000 to 4,252 in 2025: up 12.3%. The 2000, 2010 and 2020 figures are census counts, each for Monmouth 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 Monmouth?
The median resident of Monmouth is 46.2 years old; 19.0% are under 18 and 18.4% are 65 or older. The largest group is non-Hispanic white residents at 94.8%, then non-Hispanic residents of two or more races at 3.1%.
| Measure | Monmouth | Kennebec County | Change since 2015-2019 |
|---|---|---|---|
| Median age | 46.2±1.5 | 43.7 | no clear change |
| Under 18 years | 19.0%±4.3 pts | 18.7% | – |
| 65 years and over | 18.4%±3.7 pts | 21.1% | – |
| Male | 54.4%±4.5 pts | 48.9% | – |
| Hispanic or Latino (any race) | 1.6%±1.5 pts | 2.3% | – |
| White alone, not Hispanic | 94.8%±2.8 pts | 91.8% | no clear change |
| Black or African American alone, not Hispanic | 0.6%±0.8 pts | 0.9% | – |
| Asian alone, not Hispanic | 0.0%±0.7 pts | 0.9% | – |
| American Indian and Alaska Native alone, not Hispanic | 0.0%±0.7 pts | 0.2% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0%±0.7 pts | 0.0% | – |
| Two or more races, not Hispanic | 3.1%±2.1 pts | 3.7% | – |
| Some other race alone, not Hispanic | 0.0%±0.7 pts | 0.4% | – |
| Born outside the United States | 1.4%±1.1 pts | 2.4% | – |
| Speak a language other than English at home (age 5+) | 1.9%±1.5 pts | 4.8% | – |
| Civilian veterans (age 18+) | 8.6%±3.0 pts | 9.5% | – |
| With a disability | 14.9%±4.5 pts | 16.9% | – |
| No health insurance coverage | 7.5%±5.4 pts | 5.8% | – |
| High school graduate or higher (age 25+) | 93.7%±4.0 pts | 94.8% | – |
| Bachelor's degree or higher (age 25+) | 33.6%±8.9 pts | 31.9% | +14.0 pts |
| Graduate or professional degree (age 25+) | 16.4%±8.7 pts | 12.2% | – |
| Lived in the same house a year earlier | 92.2%±4.4 pts | 88.0% | – |
| Moved from another state in the past year | 0.0%±0.1 pts | 1.9% | – |
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 Monmouth earn?
Half of Monmouth's 1,799 households earn less than $74,648 a year (±$18,044), against $69,077 in Kennebec County and $74,733 in Maine. In 2015-2019 it was $73,250 in 2024 dollars; the margins of error cannot tell the two periods apart.
| Measure | Monmouth | Kennebec County | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $74,648±$18,044 | $69,077 | no clear change |
| Mean household income | $87,303±$14,293 | $88,742 | – |
| Per capita income | $38,756±$5,682 | $38,597 | no clear change |
| People below the poverty line | 9.3%±8.0 pts | 11.6% | – |
| Children under 18 below the poverty line | 10.6%±12.2 pts | 15.1% | – |
| Households receiving SNAP | 4.4%±3.5 pts | 13.6% | – |
| Households with a computer | 97.0%±2.1 pts | 95.0% | – |
| Households with a broadband subscription | 93.5%±4.4 pts | 91.1% | – |
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 Monmouth?
Owners occupy 79.8% of Monmouth's occupied homes and renters 20.2%. The median owner-occupied home is valued at $274,100 by its owner (±$21,353). The median renter pays $1,271 a month including utilities.
| Measure | Monmouth | Kennebec County | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $274,100±$21,353 | $238,200 | +$70,174 |
| Median gross rent | $1,271±$175 | $992 | no clear change |
| Renters paying 35% or more of income on rent | 52.2%±34.6 pts | 38.5% | – |
| Median monthly owner costs, with a mortgage | $1,627±$123 | $1,499 | – |
| Owner-occupied homes | 79.8%±10.6 pts | 73.7% | no clear change |
| Renter-occupied homes | 20.2%±10.6 pts | 26.3% | – |
| Housing units | 2,197±206 | 63,521 | no clear change |
| Homeowner vacancy rate | 0.0%±1.9 pts | 0.9% | – |
| Rental vacancy rate | 0.0%±7.3 pts | 1.8% | – |
| Single-family detached homes | 70.2%±8.9 pts | 67.7% | – |
| Mobile homes | 21.3%±9.4 pts | 9.9% | – |
| Built 2020 or later | 0.3%±0.6 pts | 1.0% | – |
| Built 2010 to 2019 | 9.6%±4.8 pts | 5.7% | – |
| Built 1939 or earlier | 15.9%±5.6 pts | 22.5% | – |
| Households with no vehicle | 2.2%±2.9 pts | 7.5% | – |
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 Monmouth building?
Builders took permits for 20 new housing units in Monmouth in 2025 (20 in single-family houses), 4.7 per 1,000 residents against 4.9 across Maine.
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 Monmouth work and get to work?
67.4% of Monmouth's workers drive alone and 23.0% work from home. The average trip to work takes 30.0 minutes.
| Measure | Monmouth | Kennebec County | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 64.3%±8.8 pts | 60.1% | – |
| Unemployment rate | 0.1%±0.6 pts | 3.9% | – |
| Drove alone to work | 67.4%±10.2 pts | 73.7% | – |
| Carpooled | 9.0%±6.8 pts | 6.8% | – |
| Public transportation | 0.0%±1.2 pts | 0.2% | – |
| Walked | 0.6%±1.1 pts | 2.4% | – |
| Worked from home | 23.0%±10.2 pts | 15.3% | – |
| Mean travel time to work | 30.0 min±4.2 | 25.4 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 Monmouth?
1 census tract lies mostly in Monmouth (2020 census blocks).
| Tract | Residents, 2020-2024 | Median household income |
|---|---|---|
| Tract 130Kennebec County | 4,162 | $74,648 |
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 Monmouth) · Census block assignment files
How does Monmouth compare with other places in Maine?
By the Census Bureau's July 2025 estimates, Monmouth is the 2,658th-most populous of the 16,079 U.S. towns and townships that have one and the 65th-most populous of 454 in Maine.
Monmouth ranks 157th of 349 places in Maine with 1,000 or more residents and a reliable estimate, by median household income.
| Measure | Rank | Of |
|---|---|---|
| Population, July 2025 estimate | 65th | 454 |
| Growth 2020-2025 (PEP) | 110th | 273 |
| Residents per square mile | 167th | 353 |
| Median household income | 157th | 349 |
| Per capita income | 191st | 353 |
| Median home value | 156th | 352 |
| Median gross rent | 75th | 301 |
| Bachelor's degree or higher | 144th | 352 |
| Median age | 181st | 353 |
| Owner-occupied share | 201st | 353 |
| Work from home | 39th | 275 |
| Travel time to work | 92nd | 352 |
Monmouth's figures with every place in Maine (CSV)
Every place in Maine, sortable · Compare Monmouth 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 Monmouth?
23 of the 57 figures for Monmouth 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 Monmouth 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.