St. Clair ZIP codes — St. Clair County, Illinois

St. Clair County is a mid-size city in Illinois, with 254,777 residents counted in the Census American Community Survey 2019-2023 ACS 5-year estimates. The median age here is 39.5 years against 39.1 nationally, a slightly older profile than the country as a whole. At this size the Census also publishes one-year estimates; the five-year values used here are steadier and let you compare against smaller neighbours on the same basis.

Households in St. Clair County earn a median of $70,178 a year, 10.6% below the national figure of $78,538. The median is the midpoint household, not an average, so a handful of very high earners cannot drag it upward the way they distort a mean. Poverty reaches 13.6% of residents here, above the 12.4% national rate.

The typical owner-occupied home in St. Clair County is valued at $168,800, 44.4% below the national figure, while median gross rent runs $1,032 a month, 26.6% below the national figure, or roughly $12,384 across a full year. A household on the local median income would put about 17.6% of gross pay toward that rent against the federal 30% cost-burden threshold, so renting here is cheap relative to what people here earn. The home-price-to-income ratio works out to 2.4×, against roughly 3.9× nationally, so purchase prices are unusually low against local pay, the pattern in places where supply is plentiful and wage growth has been flat. 67.8% of occupied homes are owner-occupied versus 65% nationally, so the market leans toward owners. The rent line includes utilities paid by the tenant, a definition worth remembering when comparing it against a landlord's quoted rate.

Every value on this page is published directly by the Census for this area — nothing is modelled or interpolated. Small-area estimates still carry wider margins of error than state or national figures, so check the linked ACS tables before relying on them for lending, appraisal or legal work.