Town · Maine

South Thomaston, Maine

South Thomaston, town, in Knox County, Maine. South Thomaston had 1,520 residents on July 1, 2025 by the Census Bureau's estimate, up 0.9% since 2020; the 2020 Census counted 1,511 and the ACS 2020-2024 5-year estimates put it at 1,381 (±260). GEOID 2301372585.

Residents, July 2025 estimate

1,520

Census Bureau estimate (no margin published)
2020 Census count: 1,511 · ACS 2020-2024: 1,381 ±260

Median household income

$86,838

±$7,037 (90% margin)
Maine: $74,733

Median home value

$341,300

±$37,168 (90% margin)
Maine: $296,600

Median gross rent

$925

±$633 (90% margin)
Maine: $1,139

Where is South Thomaston and what county is it in?

South Thomaston is a town in Knox County, Maine. It covers 11.4 square miles of land, 132 residents per square mile in 2020.

South Thomaston (marked with a dot) in Knox County, Maine. Boundaries: Census Bureau 2024.

Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files

How many people live in South Thomaston, and is it growing?

The Census Bureau estimates that 1,520 people lived in South Thomaston on July 1, 2025, up 0.9% since 2020, slower than Maine (+3.8%). The 2020 Census counted 1,511 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 1,381 (±260).

  • July 2020→2021 +39 (1,551)
  • 2021→2022 +1 (1,552)
  • 2022→2023 −15 (1,537)
  • 2023→2024 −14 (1,523)
  • 2024→2025 −3 (1,520)
ACS 2020-2024 5-year estimates (counts) with the change from 2015-2019
MeasureSouth ThomastonKnox CountyMaineChange since 2015-2019
Total population1,381±26041,0031,387,817no clear change
Households611±8518,484597,159no clear change
Average household size2.26±0.282.122.26no clear change
Housing units812±9224,564751,876no clear change

South Thomaston's population since 2000

From 1,416 in 2000 to 1,520 in 2025: up 7.3%. The 2000, 2010 and 2020 figures are census counts, each for South Thomaston 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.

  • 2000 Census 1,416
  • 2005 (estimate) 1,518
  • 2010 Census 1,558
  • 2015 (estimate) 1,610
  • 2020 Census 1,511
  • 2025 (estimate) 1,520

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 South Thomaston?

The median resident of South Thomaston is 54.3 years old; 13.8% are under 18 and 34.8% are 65 or older. The largest group is non-Hispanic white residents at 96.9%, then non-Hispanic residents of two or more races at 2.2%.

Age, origin, education and moves, ACS 2020-2024 5-year estimates. Race groups are non-Hispanic; Hispanic includes any race.
MeasureSouth ThomastonKnox CountyMaineChange since 2015-2019
Median age54.3±11.349.544.8no clear change
Under 18 years13.8%±4.0 pts16.8%18.1%–
65 years and over34.8%±7.6 pts27.9%22.4%–
Male45.6%±4.8 pts50.2%49.3%–
Hispanic or Latino (any race)0.0%±2.0 pts1.9%2.2%–
White alone, not Hispanic96.9%±2.0 pts93.2%89.9%no clear change
Black or African American alone, not Hispanic0.0%±2.0 pts0.3%1.8%–
Asian alone, not Hispanic0.0%±2.0 pts0.5%1.1%–
American Indian and Alaska Native alone, not Hispanic0.0%±2.0 pts0.1%0.3%–
Native Hawaiian and Other Pacific Islander alone, not Hispanic0.4%±0.5 pts0.0%0.0%–
Two or more races, not Hispanic2.2%±1.7 pts3.8%4.2%–
Some other race alone, not Hispanic0.5%±0.7 pts0.2%0.4%–
Born outside the United States0.3%±0.4 pts3.1%4.1%–
Speak a language other than English at home (age 5+)3.5%±2.4 pts4.2%6.0%–
Civilian veterans (age 18+)10.5%±3.5 pts8.7%8.4%–
With a disability19.8%±5.6 pts13.0%15.8%–
No health insurance coverage4.6%±2.3 pts5.5%6.2%no clear change
High school graduate or higher (age 25+)96.9%±1.8 pts94.8%94.8%–
Bachelor's degree or higher (age 25+)44.6%±7.4 pts39.7%36.2%+14.2 pts
Graduate or professional degree (age 25+)15.7%±4.6 pts15.3%13.7%–
Lived in the same house a year earlier90.5%±5.2 pts90.3%89.4%–
Moved from another state in the past year2.7%±2.8 pts3.1%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 South Thomaston earn?

Half of South Thomaston's 611 households earn less than $86,838 a year (±$7,037), against $74,096 in Knox County and $74,733 in Maine. In 2015-2019 it was $85,030 in 2024 dollars; the margins of error cannot tell the two periods apart. 4.2% of residents live below the poverty line.

Income and poverty in 2024 dollars, ACS 2020-2024 5-year estimates; 2015-2019 dollars adjusted with the R-CPI-U-RS
MeasureSouth ThomastonKnox CountyMaineChange since 2015-2019
Median household income$86,838±$7,037$74,096$74,733no clear change
Mean household income$105,156±$13,055$99,101$100,102–
Per capita income$47,343±$6,012$44,763$43,742no clear change
People below the poverty line4.2%±1.9 pts8.2%10.7%no clear change
Children under 18 below the poverty line5.0%±6.2 pts6.4%13.1%–
Households receiving SNAP7.0%±4.8 pts8.5%12.0%–
Households with a computer93.6%±3.8 pts94.8%94.9%–
Households with a broadband subscription92.3%±3.9 pts90.3%90.3%–

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 South Thomaston?

Owners occupy 92.5% of South Thomaston's occupied homes and renters 7.5%. The median owner-occupied home is valued at $341,300 by its owner (±$37,168).

Housing, ACS 2020-2024 5-year estimates. Home values are owners' own estimates.
MeasureSouth ThomastonKnox CountyMaineChange since 2015-2019
Median home value (owner-occupied)$341,300±$37,168$324,900$296,600+$55,164
Median gross rent$925±$633$1,165$1,139–
Renters paying 35% or more of income on rent42.4%±33.7 pts36.3%37.9%–
Median monthly owner costs, with a mortgage$1,628±$152$1,691$1,729–
Owner-occupied homes92.5%±3.5 pts78.7%74.3%no clear change
Renter-occupied homes7.5%±3.5 pts21.3%25.7%–
Housing units812±9224,564751,876no clear change
Homeowner vacancy rate1.6%±2.5 pts0.9%0.7%–
Rental vacancy rate20.7%±26.3 pts3.3%4.2%–
Single-family detached homes90.6%±4.1 pts79.4%70.0%–
Mobile homes5.4%±3.1 pts5.8%8.2%–
Built 2020 or later2.5%±1.9 pts0.6%1.4%–
Built 2010 to 20196.5%±3.3 pts5.3%7.1%–
Built 1939 or earlier18.7%±5.6 pts32.9%22.9%–
Households with no vehicle2.5%±1.8 pts5.4%6.8%–

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 South Thomaston building?

Builders took permits for 3 new housing units in South Thomaston in 2025 (3 in single-family houses), 2.0 per 1,000 residents against 4.9 across Maine.

  • 2019 14 units
  • 2020 16 units
  • 2021 5 units
  • 2022 4 units
  • 2023 (1 months) 3 units
  • 2024 3 units
  • 2025 3 units

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 South Thomaston work and get to work?

81.9% of South Thomaston's workers drive alone and 8.3% work from home. The average trip to work takes 15.7 minutes.

Work and commuting, ACS 2020-2024 5-year estimates (workers 16 and over)
MeasureSouth ThomastonKnox CountyMaineChange since 2015-2019
In the labor force (age 16+)56.1%±7.4 pts58.1%61.7%–
Unemployment rate0.0%±4.0 pts3.9%3.8%–
Drove alone to work81.9%±6.9 pts68.8%70.8%–
Carpooled8.3%±4.3 pts9.4%7.9%–
Public transportation0.8%±1.1 pts0.1%0.5%–
Walked0.3%±0.5 pts3.5%3.4%–
Worked from home8.3%±4.4 pts16.6%15.9%no clear change
Mean travel time to work15.7 min±1.219.6 min24.6 min−4.5 min

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 South Thomaston?

1 census tract lies mostly in South Thomaston, and 1 more reaches into it (2020 census blocks).

Census tracts in South Thomaston, ACS 2020-2024 5-year estimates
TractResidents, 2020-2024Median household incomeMedian home valueShare of tract in South Thomaston
Tract 9708Knox County2,863 $87,201 $369,50054%
Tract 9900Knox County0 not published not published3%

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 South Thomaston) · Census block assignment files

How does South Thomaston compare with other places in Maine?

By the Census Bureau's July 2025 estimates, South Thomaston is the 5,936th-most populous of the 16,079 U.S. towns and townships that have one and the 186th-most populous of 454 in Maine.

South Thomaston ranks 96th of 349 places in Maine with 1,000 or more residents and a reliable estimate, by median household income.

South Thomaston's rank in Maine (1 = highest): by population among the state's towns and townships with a 2025 estimate; by the other measures among places of 1,000+ residents with a reliable estimate
MeasureRankOf
Population, July 2025 estimate186th454
Growth 2020-2025 (PEP)213th273
Residents per square mile157th353
Median household income96th349
Per capita income90th353
Median home value96th352
Poverty rate264th277
Bachelor's degree or higher75th352
Median age49th353
Owner-occupied share32nd353
Work from home243rd275
Travel time to work321st352

South Thomaston's figures with every place in Maine (CSV)

Every place in Maine, sortable · Compare South Thomaston 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 South Thomaston?

21 of the 57 figures for South Thomaston 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 South Thomaston 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.