Seymour, Illinois Demographics & Population 2026

A note before these figures: with a population of 270, Seymour'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

Seymour is a small community located in Illinois, within Champaign County. The total population is 270. It ranks as the 1116th most populous out of 1,445 Census-designated places in Illinois.

Age Demographics

The median age in Seymour is 29.9 years. This is 23% lower than the state median of 39.0 years. With 40.0% of the population under 18, Seymour has a notably young demographic profile, suggesting a family-oriented community.

Economy, Income & Housing

The median household income in Seymour is $36,063. This is 57% lower than the state median of $83,390. It is also 55% lower than the national median of $80,734. The poverty rate stands at 17.4%. This is 47% higher than the state poverty rate of 11.8%. The survey records no unemployed residents in Seymour, which reflects the size of the sample rather than a labor market without joblessness. The median home value is $135,700. Housing costs are 48% lower than the state median of $263,300. The home-value-to-income ratio is 3.8x. 72.4% of occupied housing units are owner-occupied. This homeownership rate is 8% higher than the state average of 67.1%.

Race & Ethnicity

Every resident counted in Seymour was recorded as White (non-Hispanic). A figure of exactly 100.0% reflects a survey sample too small to capture the community's full composition rather than a precise measurement.

Education

9.9% of residents aged 25 and older hold a bachelor's degree or higher. This is 74% lower than the state rate of 37.9%. Nationally, 35.7% of adults hold at least a bachelor's degree. No surveyed resident aged 25 or older reported leaving school before earning a high school diploma, though a rate of exactly 100% reflects the limits of a small sample.

Data Sources & Methodology

All demographic data for Seymour, 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.