Topeka, Illinois Demographics & Population 2026

A note before these figures: with a population of 47, Topeka's ACS estimates come from a small number of survey responses and carry wide margins of error. Individual percentages below — particularly rates that round to 0% or 100% — are approximations, not precise measurements. See data.census.gov for the published margins of error.

Population Overview

Topeka is a small community located in Illinois, within Mason County. The total population is 47. It ranks as the 1404th most populous out of 1,445 Census-designated places in Illinois.

Age Demographics

The median age in Topeka is 45.9 years. This is 18% higher than the state median of 39.0 years. Only 14.9% of residents are under 18, indicating fewer families with children. 10.6% of residents are 75 or older, suggesting a significant retirement-age population with implications for healthcare services and senior housing.

Economy, Income & Housing

The median household income in Topeka is $77,500. This is 7% lower than the state median of $83,390. It is also 4% lower than the national median of $80,734. The ACS records no residents below the poverty line in Topeka. In a community this small the estimate rests on very few survey responses, so it should be read as an absence of measurement rather than a measured absence of poverty. The unemployment rate is 41.4%. This is 609% higher than the state rate of 5.8%. The median home value is $31,300. Housing costs are 88% lower than the state median of $263,300. With a home-value-to-income ratio of just 0.4x, Topeka is one of the most affordable housing markets in the area. 56.3% of occupied housing units are owner-occupied. This homeownership rate is 16% lower than the state average of 67.1%.

Race & Ethnicity

Topeka has a predominantly White (non-Hispanic) population, comprising 93.6% of all residents. The White (non-Hispanic) population is significantly higher than the state average (93.6% vs 58.1%).

Education

0.0% of residents aged 25 and older hold a bachelor's degree or higher. This is among the lowest rates in the state, which may correlate with employment and income patterns. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 59.5%.

Data Sources & Methodology

All demographic data for Topeka, Illinois is sourced from the U.S. Census Bureau's American Community Survey (ACS) 2020–2024 5-Year Estimates. The ACS collects data from approximately 3.5 million households annually and pools five years of responses so that even small communities can be measured, though the margin of error widens as the population falls. Comparisons are made against Illinois state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 1,445 Census-designated places in Illinois. Read more about how these figures are produced on our methodology page, or visit data.census.gov for official data.