St. Marys Population

1880–2026

2,795

2026 projection

1.3% since 2020 (increase)

05001K1.5K2K2.5K3K18801900192019401960198020002020

Source: U.S. Census Bureau decennial counts and annual estimates, including 2010–2020 intercensal estimates. 2026 is a projection. Values between recorded years are interpolated.

Use the left and right arrow keys to inspect population observations.

Population by year

Population estimates for St. Marys. Annual change is shown as a percentage. Growth is the total change since the preceding observation.
20262,795+50.18%
20252,790+100.36%
20242,780+130.47%
20232,767-130.47%
20222,780+100.36%
20212,770+110.40%
20202,759+40.15%
20192,755+10.04%
20182,754-40.15%
20172,75800.00%

Showing 10 of 30 years.

The 2020 row compares the April 1 Census count with the July 1, 2019 estimate (about nine months). Its Growth and Annual change therefore do not represent a full year.

Growth since 2020, compared

St. Marys is growing about as fast as Kansas, and slower than Pottawatomie County and the U.S.

  • Pottawatomie County+6.9%
  • United States+3.1%
  • Kansas+1.3%
  • St. Marys+1.2%

Change from July 1, 2020 to July 1, 2025 population estimates—not annualized growth or site projections.

Source: U.S. Census Bureau. U.S. totals are summed from the 50 states and D.C.; unavailable comparisons are omitted.

St. Marys Demographics

26.6median age

Median age

Female28.3 yrs
Male25.8 yrs

Adults

2,091
342 seniors (65+) · 16% of adults1,749 other adults

Sex

Female 47.3% · 1,320Male 52.7% · 1,468

U.S. Census Bureau, 2024 ACS 5-year estimates · Table S0101

Race and ethnicity

Tap a square or a group below to highlight it.

Each square is about 1% of residents (roughly 28 people).

Hispanic or Latino residents can be of any race. All other groups exclude Hispanic residents.

U.S. Census Bureau, 2024 ACS 5-year estimates · Table B03002

St. Marys Income

$76,771median household income

Median household income

$76,771

Half of households earn more, half earn less

Median earnings

$47,464

Typical yearly pay for a worker 25 or older.

Poverty rate

8.6%

About 1 in 12 residents

U.S. Census Bureau, 2024 ACS 5-year estimates · Tables S1901, S1501, S1701

St. Marys Marital Status

51% of residents age 15 and older are married.

MarriedNever married
Overall
Male
Female
Marital status of residents age 15 and older
StatusOverallMaleFemale
Married51%57%46%
Never married39%38%40%
Divorced5%4%5%
Widowed4%1%6%
Separated1%0%3%

U.S. Census Bureau, 2024 ACS 5-year estimates · Table S1201