How to read it
London and Chicago, side by side
Each row is one city's day, half an hour to a square, lined up by the hours along the bottom.
- 1Filled: at the desk, 9:00 to 18:00 where that city is.
- 2Grey: up early, up late, or the weekend.
- 3Outline: asleep.
- 4Red band: your slot. Read straight down to see the same moment in every city.
- 5A marks the best time for everyone; B, when there is one, the next best.
The red band is the best time to call on Wed, 21 Oct 2026: 15:00–16:00 in London, which is 09:00–10:00 in Chicago.
Through the year
How the gap between London and Chicago moves
Chicago is 6h behind London today. Daylight saving moves it:
- Chicago 6h behind London
- Chicago 5h behind London
- Sun, 25 Oct 2026 London's clocks go back an hour. Chicago is then 5h behind London.
- Sun, 1 Nov 2026 Chicago's clocks go back an hour. Chicago is then 6h behind London.
- Sun, 14 Mar 2027 Chicago's clocks go forward an hour. Chicago is then 5h behind London.
- Sun, 28 Mar 2027 London's clocks go forward an hour. Chicago is then 6h behind London.
Hour by hour
London to Chicago time, hour by hour
On a working day (Wed, 21 Oct 2026), with working hours of 9:00 to 18:00 in both cities.
- London starts work 09:00 03:00 in Chicago Asleep
- Chicago starts work 09:00 15:00 in London At desk
- London finishes work 18:00 12:00 in Chicago At desk
- Chicago finishes work 18:00 00:00 Wed in London Asleep
Show all 24 hours
| London | Chicago |
|---|---|
| 00:00 Asleep | 18:00 Tue Late |
| 01:00 Asleep | 19:00 Tue Late |
| 02:00 Asleep | 20:00 Tue Late |
| 03:00 Asleep | 21:00 Tue Late |
| 04:00 Asleep | 22:00 Tue Asleep |
| 05:00 Asleep | 23:00 Tue Asleep |
| 06:00 Asleep | 00:00 Asleep |
| 07:00 Early | 01:00 Asleep |
| 08:00 Early | 02:00 Asleep |
| 09:00 At desk | 03:00 Asleep |
| 10:00 At desk | 04:00 Asleep |
| 11:00 At desk | 05:00 Asleep |
| 12:00 At desk | 06:00 Asleep |
| 13:00 At desk | 07:00 Early |
| 14:00 At desk | 08:00 Early |
| 15:00 At desk | 09:00 At desk |
| 16:00 At desk | 10:00 At desk |
| 17:00 At desk | 11:00 At desk |
| 18:00 Late | 12:00 At desk |
| 19:00 Late | 13:00 At desk |
| 20:00 Late | 14:00 At desk |
| 21:00 Late | 15:00 At desk |
| 22:00 Asleep | 16:00 At desk |
| 23:00 Asleep | 17:00 At desk |
Questions
Questions people ask
What is the time difference between London and Chicago?
Chicago is 6h behind London (as of Wed, 21 Oct 2026). That changes on Sun, 25 Oct 2026, when London's clocks go back: then Chicago is 5h behind London.
What is the best time for a call between London and Chicago?
On a working day, the best time for a call is 15:00–16:00 in London (09:00–10:00 in Chicago) until 24 Oct 2026 and from 1 Nov 2026 to 13 Mar 2027 and from 28 Mar 2027, and 14:00–15:00 in London (09:00–10:00 in Chicago) from 25 Oct 2026 to 31 Oct 2026 and from 14 Mar 2027 to 27 Mar 2027.
Does London change its clocks?
Yes. London moves its clocks back an hour on Sun, 25 Oct 2026, and forward an hour on Sun, 28 Mar 2027.
Does Chicago change its clocks?
Yes. Chicago moves its clocks back an hour on Sun, 1 Nov 2026, and forward an hour on Sun, 14 Mar 2027.
More city pairs
Compare more cities
London and…
- London and Mumbai
- London and Delhi
- London and Bengaluru
- London and Dubai
- London and Abu Dhabi
- London and Riyadh
- London and Doha
- London and Singapore
- London and Hong Kong
- London and Tokyo
- London and Sydney
- London and Paris
- London and Berlin
- London and Amsterdam
- London and New York
- London and Toronto
- London and Los Angeles
- London and San Francisco
Chicago and…
- Chicago and Mumbai
- Chicago and Delhi
- Chicago and Bengaluru
- Chicago and Dubai
- Chicago and Abu Dhabi
- Chicago and Riyadh
- Chicago and Doha
- Chicago and Singapore
- Chicago and Hong Kong
- Chicago and Tokyo
- Chicago and Sydney
- Chicago and Paris
- Chicago and Berlin
- Chicago and Amsterdam
- Chicago and New York
- Chicago and Toronto
- Chicago and Los Angeles
- Chicago and San Francisco
From the team behind 10:10
Running an event across time zones?
C4E has spent twenty years running conferences, dealer meets and offsites in more than 40 countries, with clients, speakers and crews in different time zones. 10:10 is one of the tools we built for our own shows. It is free, with no account and nothing upsold.