London time to UTC time
UTC is 0 hours ahead of London in January and 1 hour behind in July (London BST/UTC+01:00 in summer; UTC UTC/UTC+00:00). Enter a London time below to convert it, or leave it blank to see the current time in both cities.
How to use the London to UTC time
- Type a London time (24-hour) and optionally a date, or leave blank for now.
- Click Convert.
- Read the UTC time and the working-hours table.
Time difference between London and UTC
UTC is 0 hours ahead of London in January and 1 hour behind in July. London observes daylight saving time and UTC does not, so the difference changes twice a year. London uses Europe/London time (UTC+00:00 in January, UTC+01:00 in July); UTC uses UTC (UTC+00:00 in January, UTC+00:00 in July).
Working week in London and UTC
London: Office hours 09:00–17:30, weekend Saturday–Sunday. Clocks go forward on the last Sunday of March (BST, UTC+1) and back on the last Sunday of October (GMT).
UTC: Coordinated Universal Time never changes and has no daylight saving. It is the reference for aviation, servers, logs and international scheduling; London matches it only in winter.
Quick conversion table (summer difference)
| London | UTC |
|---|---|
| 08:00 | 07:00 |
| 09:00 | 08:00 |
| 10:00 | 09:00 |
| 12:00 | 11:00 |
| 14:00 | 13:00 |
| 16:00 | 15:00 |
| 18:00 | 17:00 |
| 20:00 | 19:00 |
| 22:00 | 21:00 |
Table uses the July difference; the tool above applies the exact rule for any date.
Best time to call between London and UTC
Within normal office hours (09:00–18:00) in both cities: 10:00–17:00 London time. For a compromise outside that window, the fairest slots are the ones nearest each side's start or end of day, alternating who takes the inconvenient hour.
Reverse
Need the other direction? See UTC to London, or the general time zone converter.
Frequently asked questions
How many hours ahead is UTC from London?
UTC is 0 hours ahead of London in January and 1 hour behind in July.
When it is 12:00 noon in London, what time is it in UTC?
11:00 in summer (the same or previous day); use the tool for a specific date.
Does the converter handle daylight saving?
Yes, for the exact date you enter, using the IANA time-zone rules in your browser.
Privacy
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Last updated 2026-09-23.