Chicago Time Now

What this page shows

So you want to know what time it is in Chicago right now. Maybe you have a call with someone in the Midwest, a flight to catch, a game starting on local time, or someone to reach before their evening is over. That is what the clock at the top of this page is for. It shows the current time in Chicago and ticks forward every second, so there is nothing for you to work out by hand.

Wherever in the world you are reading this from, the clock tracks Chicago and keeps itself right on its own, even across the days when the clocks change. Whether the city is on its winter or its summer setting at the time, the clock shows the correct local time.

Chicago changes its clocks twice a year

Here is the part worth knowing about Chicago time. The city does not stay on the same clock all year. It uses Central Standard Time, CST, through the winter, and moves an hour ahead to Central Daylight Time, CDT, for the summer.

So there are two settings behind Chicago time:

• CST, Central Standard Time. Six hours behind UTC, written UTC minus 6. The winter setting, from early November to early March.
• CDT, Central Daylight Time. Five hours behind UTC, written UTC minus 5. The summer setting, from early March to early November.

The clock above follows whichever one is in force, so you do not have to track it yourself. The section further down spells out the dates if you ever need to work it out for a particular day.

What time zone Chicago is in

Chicago runs on Central Time, the zone of the American heartland, six hours behind UTC in winter and five hours behind in summer. It is the second most populated of the US zones, covering a broad swathe of the country from the Gulf Coast up to the Canadian border, including Houston, Dallas, and New Orleans.

Chicago is the city that anchors Central Time, and the zone turns up more often than you might expect. American television listings are quoted against it, in the familiar "8/7 Central" form, meaning 8 o'clock Eastern and 7 o'clock Central. The city is also a heart of the futures markets, with the long-running Chicago exchanges, so a good deal of the financial day is timed from here as well.

How to tell if Chicago is on CST or CDT right now

Chicago changes its clocks on two Sundays a year, and the dates are set in US law, the Uniform Time Act, last amended by the Energy Policy Act of 2005. They are different from the European dates, landing a little wider on each side:

• Spring forward. On the second Sunday of March, at 2 in the morning, the clocks jump ahead one hour. CST becomes CDT, and Chicago goes from UTC minus 6 to UTC minus 5.
• Fall back. On the first Sunday of November, at 2 in the morning, the clocks drop back one hour. CDT becomes CST again, at UTC minus 6.

So the rule is short. From the second Sunday of March to the first Sunday of November, Chicago is on CDT. The rest of the year, early November round to early March, it is on CST. Place today between those two Sundays and you have your answer.

Time difference from Chicago to other cities

The cities that share North America's daylight saving schedule stay a fixed distance from Chicago all year, while the ones on different schedules can shift by an hour at the edges of the seasons. Here is the quick reference, assuming it is 12 noon in Chicago.

A few quick examples

Let us run a few, so you can see how this works.

Say it is 12 noon in Chicago. New York is one hour ahead all year, so 1 in the afternoon on the East Coast, and Los Angeles is two hours behind at 10 in the morning. In the winter, London is six hours ahead, making it 6 in the evening there.

Now a call to London, which has one small catch. The US and the UK both change their clocks, but not on the same dates, so for a couple of short windows in spring and autumn the usual six hour gap briefly narrows to five. For anything that has to land exactly in those weeks, trust the live clock over the rule of thumb.

And one for Asia, which is the real challenge. Tokyo is fifteen hours ahead of Chicago in winter, so 12 noon here is 3 in the morning the next day in Tokyo. There is almost no shared working hour, so those calls usually fall in the early morning or late evening for one side.

A couple of things about Chicago time

Chicago sits at about 42 degrees north, so the length of the day swings a fair amount across the year. Around midsummer there are roughly fifteen hours between sunrise and sunset, while around midwinter that drops to a little over nine hours, with the sun setting in the late afternoon.

On the clock-against-sun question, Chicago is a close match. The city sits only a little east of the meridian Central Standard Time is built on, so in winter the sun is at its highest within about ten minutes of 12 noon by the clock. In summer, on CDT, the clock runs an hour ahead of the sun, like the rest of the country, which is the point of the change: more daylight in the evening.

The zones on either side

Chicago anchors Central Time, with the neighbouring US zones an hour away on each side. Here are the zones to compare against:

• EST Time Now, Eastern Time, one hour ahead
• PST Time Now, Pacific Time, two hours behind

For the country as a whole, see USA time now, and for the global reference these are measured from, UTC Time Now.

Questions people ask

What time is it in Chicago right now?

The clock near the top of this page is the answer, and it updates every second. Just remember that Chicago changes its clocks, so it shows CST through the winter and CDT through the summer, switching over on its own. Either way, the time shown is the correct Chicago time.

Is Chicago on CST or CDT right now?

Go by the dates. Chicago is on CDT from the second Sunday of March to the first Sunday of November. The rest of the year, from early November round to early March, it is on CST. Find where today falls between those two Sundays and you will know.

How many hours behind New York is Chicago?

One hour behind, all year. Both change their clocks on the same dates, so the one hour gap between Central and Eastern never changes.

What time zone is Chicago in?

Central Time, six hours behind UTC in winter and five hours behind in summer. It is the same zone as Houston, Dallas, and New Orleans, the second most populated of the US zones.

What is the time difference between Chicago and London?

London is normally six hours ahead of Chicago. The two change their clocks on slightly different dates, so for a couple of short windows in spring and autumn the gap narrows to five hours.

What is the IANA name for Chicago time?

It is America/Chicago in the IANA time zone database, the time data your phone and your computer use. It carries both the CST and CDT offsets along with the rule for switching between them, and it is what drives the live clock on this page.

References

1. Internet Assigned Numbers Authority (IANA). Time Zone Database (the tz database), home of the America/Chicago identifier. https://www.iana.org/time-zones
2. U.S. Code, Title 15, Section 260a: the Uniform Time Act of 1966, as amended by the Energy Policy Act of 2005, which sets the daylight saving dates. Office of the Law Revision Counsel. https://uscode.house.gov/view.xhtml?req=granuleid:USC-prelim-title15-section260a
3. U.S. Department of Transportation, Standard Time Zone Boundaries under 49 CFR Part 71. https://www.transportation.gov/regulations/time-act
4. National Institute of Standards and Technology (NIST), Time and Frequency Division, the source of official time for the United States. https://www.nist.gov/pml/time-and-frequency-division