What Time Zone Is Chicago In? Central Time, Explained
Chicago is in the Central Time Zone. In winter it runs on Central Standard Time (CST, UTC-6); from early March to early November it observes daylight saving and switches to Central Daylight Time (CDT, UTC-5). In 2026, daylight time runs March 8 through November 1.
For quick math: Chicago is one hour behind New York and two hours ahead of Los Angeles, and those gaps hold all year because the cities change clocks on the same dates. The whole state of Illinois is Central, so every Illinois city shares Chicago's clock.
Computers and phones identify the zone as America/Chicago. If you need Chicago time in Eastern right now, the CST to EST converter applies the daylight saving rules for you.
Working across Central and Eastern? The CST to EST converter shows both clocks live, daylight saving included.
Open CST to EST Converter →CST or CDT: Which One Is Chicago On?
One zone, two names. CST is the winter offset, CDT is the summer offset, and the switch happens at 2:00 a.m. local time on the changeover dates.
| Name | Abbreviation | UTC offset | In effect (2026) |
|---|---|---|---|
| Central Standard Time | CST | UTC-6 | Jan 1 – Mar 8, then Nov 1 – Dec 31 |
| Central Daylight Time | CDT | UTC-5 | Mar 8 – Nov 1 |
People say "CST" year-round in casual conversation, and it rarely causes trouble. It can, though: schedule a call for "3 PM CST" in July and a literal reading puts it at 4 PM Chicago time. Write "CT," "Central," or just "Chicago time" and the ambiguity disappears. Time zone boundaries and daylight saving observance are administered at the federal level by the U.S. Department of Transportation; the changeover dates themselves are written into federal law.
Chicago Time vs. Other Major US Cities
The offsets below hold year-round for every city except Phoenix, because Arizona skips daylight saving while everyone else changes clocks on the same two dates.
| City | Time zone | Relative to Chicago | Noon in Chicago is |
|---|---|---|---|
| New York | Eastern | 1 hour ahead | 1:00 p.m. |
| Washington, DC | Eastern | 1 hour ahead | 1:00 p.m. |
| Denver | Mountain | 1 hour behind | 11:00 a.m. |
| Phoenix | Mountain (no DST) | 1 hour behind in winter, 2 in summer | 11:00 a.m. winter / 10:00 a.m. summer |
| Los Angeles | Pacific | 2 hours behind | 10:00 a.m. |
The New York gap is the one that matters most in practice — East Coast market hours, network TV feeds, and most corporate head offices run one hour ahead of Chicago, every day of the year.
Other Cities on Chicago's Clock
The Central zone runs from the Gulf Coast to the Canadian border. If your call, flight, or game involves any of these cities, no conversion is needed — 9:00 a.m. there is 9:00 a.m. in Chicago:
- Dallas and Houston
- Minneapolis
- Kansas City
- New Orleans
- Memphis
- Milwaukee
- Oklahoma City
Milwaukee is the useful one to remember for day trips: about 90 miles north, same clock.
What 8/7c Means: Chicago Gets Prime Time an Hour Early
National TV listings like "8/7c" mean 8:00 Eastern, 7:00 Central. A show promoted for "8/7c" airs at 7:00 p.m. in Chicago.
The consequence: prime time in Chicago runs 7:00–10:00 p.m., not the 8:00–11:00 p.m. block East Coast viewers see. Network late-night shows start at 10:35 p.m. instead of 11:35 p.m.
Live events shift the same way. An NFL Sunday night kickoff listed at 8:20 p.m. ET starts at 7:20 p.m. on Chicago screens, and the live Times Square ball drop hits Chicago TVs at 11:00 p.m. on New Year's Eve. If an event is broadcast live, subtract one hour from the Eastern listing — always.
Illinois Is Simple. Indiana Is Not.
Every inch of Illinois is Central — Chicago, Springfield, Rockford, Carbondale. Cross the state line into Indiana and it gets complicated.
Most of Indiana runs on Eastern Time, including Indianapolis. But the northwest corner of the state — Gary, Hammond, and the rest of the Chicago metro spillover — stays on Central so the region keeps one clock. (A pocket in southwest Indiana around Evansville is Central too.)
In practice: drive from Chicago to Gary and your phone doesn't move. Drive from Chicago to Indianapolis and you lose an hour somewhere around the zone boundary. Plan arrival times accordingly — a "3-hour" drive to Indianapolis lands you there four clock-hours later.
Scheduling and Travel Notes
A few specifics that save real mistakes:
- Phones and laptops handle it. Any device set to update automatically uses America/Chicago and switches between CST and CDT on its own.
- Flight times are local at each airport. A ticket out of O'Hare or Midway shows Central time for departure and the destination's local time for arrival. Nothing on the itinerary needs converting.
- Calendar invites beat abbreviations. Create events in your calendar app with the zone attached ("Central Time – Chicago") rather than typing "CST" into the description.
- For international scheduling, anchor on UTC. Chicago is UTC-6 in winter and UTC-5 in summer; give the UTC time and let each side convert. The official US clock is at time.gov, run by NIST.
Frequently asked questions
What is the IANA time zone name for Chicago?
America/Chicago. That is the identifier operating systems, programming languages, and scheduling tools use for the US Central zone. Prefer it over a fixed offset like UTC-6 in code or server settings: the identifier tracks daylight saving automatically, so timestamps stay correct when clocks shift in March and November. A hardcoded -6 offset is wrong for roughly eight months of the year.
Is Chicago in the same time zone as Texas?
Almost all of it. Dallas, Houston, Austin, and San Antonio are Central, so their clocks match Chicago's to the minute all year. The exception is the far western tip of the state: El Paso and Hudspeth County run on Mountain Time, one hour behind Chicago. For anywhere in Texas other than the El Paso area, assume Chicago time.
How many hours behind London is Chicago?
Six hours for most of the year. Chicago is UTC-6 in winter and UTC-5 in summer, while London is UTC+0 and UTC+1, so the two daylight shifts roughly cancel out. The gap briefly narrows to five hours in March and again in late October, because the US changes clocks on different dates than the UK — March 8 and November 1 in 2026, versus late March and late October in Britain.
When did Chicago start using Central Time?
In November 1883, when the railroads of the United States and Canada replaced hundreds of local sun-based times with a system of standard time zones, and Chicago fell squarely in the Central one. Congress wrote the system into federal law with the Standard Time Act of 1918 and standardized daylight saving with the Uniform Time Act of 1966. Chicago's zone assignment has not changed since the railroad era.
Will Chicago ever stop changing its clocks?
Not without an act of Congress. Federal law lets a state opt out of daylight saving and stay on standard time year-round — Arizona and Hawaii do — but it does not let a state adopt permanent daylight time on its own. Illinois lawmakers have proposed permanent daylight saving more than once, but none of those bills can take effect until federal law changes. Until then, Chicago springs forward in March and falls back in November.
Working across Central and Eastern? The CST to EST converter shows both clocks live, daylight saving included.
Open CST to EST Converter →