Illinois · IL · Time & calendar
Illinois: Does the state observe daylight saving time?
Observes DST
Illinois observes daylight saving time and has not enacted a law to change that.
Federal law puts a state on daylight saving time unless it passes a law opting out, and federal sources list only Hawaii and Arizona as states that opt out. This answer is an inference: Illinois is not on the federal list of exceptions, and no enacted Illinois law for year-round time was found. Bills to adopt permanent daylight saving time have been filed in Illinois but have not become law.
What the law says
DST is not observed in Hawaii, American Samoa, Guam, Puerto Rico, the Virgin Islands and the state of Arizona (with the exception of the Navajo Indian Reservation, which does observe DST).
Sources
- NIST: Daylight Saving Time Official · nist.gov
- 15 U.S.C. ยง 260a (Uniform Time Act) Mirror of official text · law.cornell.edu
- NCSL: Daylight Saving Time State Legislation Secondary · ncsl.org
- U.S. Department of Transportation: Daylight Saving Time Official · transportation.gov
Confirm with the state
- Agency
- Illinois General Assembly
- Website
- ilga.gov
How bordering states compare
- Indiana Observes DSTIndiana observes daylight saving time statewide and has not enacted a law to change that.
- Iowa Observes DSTIowa observes daylight saving time under state law and has not enacted a law to change that.
- Kentucky Observes DSTKentucky observes daylight saving time and has not enacted a law to change that.
- Missouri Observes DSTMissouri observes daylight saving time; no law to change that has been enacted, though the House passed a trigger bill in 2026.
- Wisconsin Observes DSTWisconsin observes daylight saving time by statute and has not passed a law to change that.