Greenwich Mean Time
GMT means UTC throughout the year.
TIME ZONE CONVERTER
London to GMT
Time Converter
Convert London, United Kingdom to Greenwich Mean Time. Compare dates, seasonal differences and meeting hours.
London is 0h or 1h ahead of GMT in 2026, depending on the date.
9 AM London = 9 AM GMT
Selected date: November 4, 2026. Fixed abbreviations retain their stated UTC offsets.
THE QUICK REFERENCE
CSVLondon to GMT conversion table
November 4, 2026 · Date changes are marked.
View the full 24-hour table
| London | GMT |
|---|---|
| 12:00 AM | 12:00 AM |
| 1:00 AM | 1:00 AM |
| 2:00 AM | 2:00 AM |
| 3:00 AM | 3:00 AM |
| 4:00 AM | 4:00 AM |
| 5:00 AM | 5:00 AM |
| 6:00 AM | 6:00 AM |
| 7:00 AM | 7:00 AM |
| 8:00 AM | 8:00 AM |
| 9:00 AM | 9:00 AM |
| 10:00 AM | 10:00 AM |
| 11:00 AM | 11:00 AM |
| London | GMT |
|---|---|
| 12:00 PM | 12:00 PM |
| 1:00 PM | 1:00 PM |
| 2:00 PM | 2:00 PM |
| 3:00 PM | 3:00 PM |
| 4:00 PM | 4:00 PM |
| 5:00 PM | 5:00 PM |
| 6:00 PM | 6:00 PM |
| 7:00 PM | 7:00 PM |
| 8:00 PM | 8:00 PM |
| 9:00 PM | 9:00 PM |
| 10:00 PM | 10:00 PM |
| 11:00 PM | 11:00 PM |
Starting with the GMT working day
These examples start on 2026-11-04 in GMT.
09:00 GMT09:00 →London · 2026-11-04
17:00 GMT17:00 →London · 2026-11-04
Which time-zone meaning are we using?
ONE CLOCK TIME. THE WHOLE YEAR.
Year CSV09:00 London to GMT throughout 2026
Keeping 09:00 on the London clock produces 2 different destination clock/date answers in 2026. The ranges below use London calendar dates, including transition days.
| Dates in London · 2026 | GMT answer | Source → destination offsets | Explore |
|---|---|---|---|
| Jan 1 – Mar 2887 dates | 09:00Same date | UTC → UTC | |
| Mar 29 – Oct 24210 dates | 08:00Same date | UTC+01:00 → UTC | |
| Oct 25 – Dec 3168 dates | 09:00Same date | UTC → UTC |
Every calendar date is included, not just workdays. Date ranges include both endpoints. Based on IANA 2026e; future rules may change.
DON’T LOSE A DAY
When does London time become a different date in GMT?
Your complete source day: 2026-11-04. Each range shows which destination date to use.
London · 2026-11-0400:00–24:00UTC
GMT · 2026-11-0400:00–24:00UTC Same date
Range starts are included; ends are excluded. 24:00 means midnight at the end of that date. Repeated hours appear separately with their UTC offsets. The strip is proportional to elapsed time.
THE BIGGER PICTURE
2026A year of time differences.
How GMT compares with London throughout 2026.
JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC
0h
−1h
0h
London changes its UTC offset in 2026. GMT is a fixed offset.
See exact change periods
| From (UTC, inclusive) | Until (UTC, exclusive) | GMT vs London |
|---|---|---|
| 1 Jan 2026, 00:00 UTC | 29 Mar 2026, 01:00 UTC | 0h difference |
| 29 Mar 2026, 01:00 UTC | 25 Oct 2026, 01:00 UTC | 1h behind |
| 25 Oct 2026, 01:00 UTC | 1 Jan 2027, 00:00 UTC | 0h difference |
CLOCK CHANGES
What changes at the next clock adjustment?
Exact periods outside the most common difference in 2026
The most frequent difference has GMT 1h behind relative to London. Exceptions:
| From (UTC, inclusive) | Until (UTC, exclusive) | Compared with London |
|---|---|---|
| 1 Jan 2026, 00:00 UTC | 29 Mar 2026, 01:00 UTC | the same time |
| 25 Oct 2026, 01:00 UTC | 1 Jan 2027, 00:00 UTC | the same time |
PLAN BEYOND A SINGLE DAY
Daily CSVLondon–GMT working hours through 2026
Every date calculated with your working windows. 261 selected London workdays; public holidays are not applied.
Least shared time7h
Most common7h
Most shared time8h
Days without a 60-min slot0 / 261
A start time that survives the whole year.
Start a 60-minute meeting in London 10:00–16:00.
These starts fit both working windows on every selected London workday in 2026, using a 15-minute start grid. The end of each range is the last valid start.
London: 09:00–17:00, Mon, Tue, Wed, Thu, Fri. GMT: 09:00–17:00, Mon, Tue, Wed, Thu, Fri.
Calculation details and repeated hours
Overnight shifts belong to their start weekday. Host workday means the source calendar date. Repeated local times use the first occurrence.
THE DETAILS THAT MATTER
London to GMT: useful answers
Why is the London to GMT difference sometimes 0 hours and sometimes 1 hour?
London is 0h or 1h ahead of GMT in 2026, depending on the date. London changes its UTC offset in 2026. GMT is a fixed offset.
Does the London–GMT time difference change in 2026?
The published rules produce 3 periods with 2 different offsets in 2026. See the annual chart for the exact boundaries of each period.
Does this conversion change the calendar date?
09:00 in London on 2026-11-04 is 09:00 in GMT on 2026-11-04. This selected time stays on the same date in both places. Other times can cross midnight.
Can London and GMT meet during working hours?
Your selected working windows share 8h on 2026-11-04. The planner above checks the whole meeting duration and shows suitable start times. Edit the windows to match your team.
Related time-zone meanings and conversions
Calculated with IANA 2026e. Working hours are your preferences; public holidays and calendar availability are not included. Our methodology