Illinois Time Zone Map
Central Time, statewide.
Time zones in Illinois
| Zone | IANA | Standard | Daylight | Abbr |
|---|---|---|---|---|
| Central Time | America/Chicago | UTC−6 | UTC−5 | CST / CDT |
Illinois is Central Time statewide (CST/CDT, UTC−6 in winter, UTC−5 in summer), with no Eastern or Mountain areas; its cities Chicago and Springfield follow the same clock.
Crossing the state line
Crossing into Indiana usually means gaining an hour, because most of Indiana is Eastern Time — but the Indiana counties around Gary and Hammond, next to Chicago, stay on Central Time, as do the counties around Evansville. Wisconsin, Iowa, Missouri, and western Kentucky all match Illinois.
Frequently asked questions
What time zone applies to Illinois?
Illinois is Central Time, statewide.
Does Illinois use a single time zone?
It does: Illinois is fully within Central Time.
What time zone is Chicago in?
Chicago is on Central Time (CST / CDT — UTC−6 in winter, UTC−5 in summer, IANA zone America/Chicago).
Sources: zone boundaries from the U.S. Department of Transportation’s time zone regulations (49 CFR Part 71); offsets and daylight saving rules from the IANA time zone database. See Data Sources for how this site uses them.