London → Chicago
United Kingdom → United States
London
United Kingdom
Chicago
United States
Chicago current time: 6h behind
Frequently Asked Questions
What is the time difference between London and Chicago?
The time difference between London (United Kingdom) and Chicago (United States) depends on the time of year due to Daylight Saving Time changes. Use the converter above to see the current difference.
Does London observe Daylight Saving Time?
Some time zones observe DST and some do not. The converter shows a DST indicator and the date of the next transition for each city.
What is the best time to call from London to Chicago?
The best time for a call is during overlapping business hours (9 AM – 6 PM) in both cities. Use the Meeting Planner tool to find the optimal window.
About Time Zone Conversions
Time zone conversion is date-sensitive. Every place has a UTC offset, but many offsets change during the year because of Daylight Saving Time, and countries do not all switch on the same dates. The IANA Time Zone Database tracks those rules for 400+ named zones and is the source used by most operating systems and programming languages. When you convert between two cities, both zones need to be evaluated for the selected date. Otherwise a city pair can be wrong by one or two hours. The converter applies IANA rules automatically, including half-hour offsets like India at UTC+5:30, quarter-hour offsets like Nepal at UTC+5:45, and regions that do not use DST.