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Europe/London time zone

12:57PMGMT

GMTUTC+0+5 h vs New York (you)

About Europe/London

Europe/London is the IANA time zone for United Kingdom, Guernsey, Isle of Man and Jersey. It currently keeps Greenwich Mean Time (GMT, UTC+0) in winter and British Summer Time (BST, UTC+1) in summer.

The zone serves 4 countries or territories because their clocks have agreed since 1970; tzdata lists them together in zone1970.tab. That says nothing about borders or sovereignty, as the file’s header points out.

Its principal location is London at 51.51° N, 0.13° W.

Abbreviations in use: GMT, BST. Offset page: UTC+0.

Rule for future years (POSIX TZ string)

GMT0BST,M3.5.0/1,M10.5.0

The standard time is called GMT and is UTC+0. POSIX writes the offset with the opposite sign (west of Greenwich is positive), which is why the string says "0". Daylight saving time is called BST and is UTC+1. It starts on the last Sunday of March at 01:00 and ends on the last Sunday of October at 02:00, local time. Software that has no full tzdata copy, such as many embedded devices, can use this string directly as the TZ environment variable.

Upcoming transitions

Computed from tzdata 2026f; local times are read on the clock just before each change.

History of Europe/London since 1970

The record starts with local mean time (UTC−0:01), which ended on December 1, 1847. The first daylight saving time in the record is in 1916.

YearsClocksAbbreviations
1970UTC+1 all yearBST
1971UTC+1 until October 31, then UTC+0BST, GMT
1972 onwardUTC+0 in winter, UTC+1 in summerGMT, BST

Before 1970

108 offset changes before 1970 in the record; the first 12 and the last 12:

Changes of the winter (standard) offset: Sunday, October 31, 1971, UTC+1 → UTC+0.

tzdata commits to accuracy from 1970 for every zone (zone1970.tab); earlier entries are historical research and may be incomplete.

Aliases and zones with the same clock

These older or country-specific IDs are links to Europe/London in tzdata. Their pages redirect here: Europe/Belfast, Europe/Guernsey, Europe/Isle_of_Man, Europe/Jersey, GB, GB-Eire.

Other zones that keep exactly the same time under the current rules (but have a different history): Atlantic/Canary, Atlantic/Faroe, Atlantic/Madeira, Europe/Dublin, Europe/Lisbon.

Places on Europe/London

Convert London time

Tip: Alt+↑/↓ steps the time by 15 minutes (Shift: one hour). The link keeps the date, time and direction.

Using Europe/London in code

Every major platform reads the same IANA ID. Store instants in UTC and convert with the ID at display time; never store a fixed offset for a place that has daylight saving time.

// JavaScript
new Date().toLocaleString('en-US', { timeZone: 'Europe/London' })

# Python 3.9+
from zoneinfo import ZoneInfo
from datetime import datetime
datetime.now(ZoneInfo('Europe/London'))

// Java
java.time.ZonedDateTime.now(java.time.ZoneId.of("Europe/London"))

// Go
loc, _ := time.LoadLocation("Europe/London")
time.Now().In(loc)

-- PostgreSQL
SELECT now() AT TIME ZONE 'Europe/London';

# Shell
TZ='Europe/London' date

Platforms ship their own copy of tzdata and update it on their own schedule. After a rule change, outputs can differ until the platform updates; this page uses tzdata 2026f.

Questions

What is the UTC offset of Europe/London?
UTC+0 in winter and UTC+1 in summer (daylight saving time from the last Sunday of March at 1:00 AM to the last Sunday of October at 2:00 AM).
Does Europe/London observe daylight saving time?
Yes: clocks move one hour forward on the last Sunday of March at 1:00 AM and back on the last Sunday of October at 2:00 AM.
Is Europe/Belfast the same as Europe/London?
Yes. Europe/Belfast, Europe/Guernsey, Europe/Isle_of_Man, Europe/Jersey, GB and GB-Eire are a link (alias) to Europe/London in tzdata and give the same time since 1970. They remain valid IDs.
Which countries use Europe/London?
United Kingdom, Guernsey, Isle of Man and Jersey, according to zone1970.tab in tzdata.

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