The time difference between Ottawa and London is 4 hours. When it is 12:00 noon in Ottawa, it is 16:00 in London. Ottawa uses the America/Toronto time zone (UTC-4), while London uses Europe/London (UTC+0).
There are 4 overlapping business hours between Ottawa and London (assuming 9:00–17:00 in each city). The ideal window for calls and meetings is:
Use this table to quickly convert any hour from Ottawa time to London time. Rows highlighted in green indicate overlapping business hours in both cities.
| Ottawa | London | |
|---|---|---|
| 00:00 | 04:00 | Night |
| 01:00 | 05:00 | Night |
| 02:00 | 06:00 | Night |
| 03:00 | 07:00 | Night |
| 04:00 | 08:00 | Night |
| 05:00 | 09:00 | Night |
| 06:00 | 10:00 | |
| 07:00 | 11:00 | |
| 08:00 | 12:00 | |
| 09:00 | 13:00 | Overlap |
| 10:00 | 14:00 | Overlap |
| 11:00 | 15:00 | Overlap |
| 12:00 | 16:00 | Overlap |
| 13:00 | 17:00 | |
| 14:00 | 18:00 | |
| 15:00 | 19:00 | |
| 16:00 | 20:00 | |
| 17:00 | 21:00 | |
| 18:00 | 22:00 | |
| 19:00 | 23:00 | |
| 20:00 | 00:00 (+1 day) | |
| 21:00 | 01:00 (+1 day) | |
| 22:00 | 02:00 (+1 day) | Night |
| 23:00 | 03:00 (+1 day) | Night |
Ottawa is currently observing daylight saving time, while London is on standard time. When Ottawa switches back to standard time, the difference between these two cities will shift by 1 hour.
The time difference is 4 hours. London is 4 hours ahead of Ottawa.
Yes. One of these cities observes DST while the other does not, so the difference shifts by 1 hour when DST begins or ends.
The best window is between 09:00 and 13:00 Ottawa time, which corresponds to 13:00–17:00 in London. Both sides fall within normal business hours.
Add 4 hours to Ottawa time to get London time. Use the hour-by-hour table above for a quick reference.
For sunrise and sunset data, visit TheSunsetTimes.com. For detailed DST schedules, see DaylightSavingTime.info.