Time zone comparison
British Summer Time (BST, UTC+01:00) vs Greenwich Mean Time (GMT, UTC+00:00). Right now BST is 1h ahead of GMT. BST is used in London, Birmingham and Manchester while GMT covers United Kingdom (winter), West Africa, Iceland. Use the 24-hour grid below to find a meeting slot both sides will tolerate.
Heads up: these zones diverge on daylight saving.
BST observes DST while GMT does not, so the gap shifts by an hour twice a year. In January the difference is 0h, in July it is 1h. If you are scheduling across the spring or autumn transitions, double-check the date.
Hours where both sides sit inside 9-to-5 business hours.
Both in business hours
10:00 BST
09:00 GMT
Both in business hours
11:00 BST
10:00 GMT
Both in business hours
12:00 BST
11:00 GMT
Each row is one hour. Green rows are when both sides are inside 9 AM to 5 PM.
| Hour | BST (British Summer Time) | GMT (Greenwich Mean Time) | Overlap |
|---|---|---|---|
| 12 AM | 00:00Thu | 23:00Wed | No overlap |
| 1 AM | 01:00Thu | 00:00Thu | No overlap |
| 2 AM | 02:00Thu | 01:00Thu | No overlap |
| 3 AM | 03:00Thu | 02:00Thu | No overlap |
| 4 AM | 04:00Thu | 03:00Thu | No overlap |
| 5 AM | 05:00Thu | 04:00Thu | No overlap |
| 6 AM | 06:00Thu | 05:00Thu | No overlap |
| 7 AM | 07:00Thu | 06:00Thu | No overlap |
| 8 AM | 08:00Thu | 07:00Thu | No overlap |
| 9 AM | 09:00Thu | 08:00Thu | BST only |
| 10 AM | 10:00Thu | 09:00Thu | Business overlap |
| 11 AM | 11:00Thu | 10:00Thu | Business overlap |
| 12 PM | 12:00Thu | 11:00Thu | Business overlap |
| 1 PM | 13:00Thu | 12:00Thu | Business overlap |
| 2 PM | 14:00Thu | 13:00Thu | Business overlap |
| 3 PM | 15:00Thu | 14:00Thu | Business overlap |
| 4 PM | 16:00Thu | 15:00Thu | Business overlap |
| 5 PM | 17:00Thu | 16:00Thu | GMT only |
| 6 PM | 18:00Thu | 17:00Thu | No overlap |
| 7 PM | 19:00Thu | 18:00Thu | No overlap |
| 8 PM | 20:00Thu | 19:00Thu | No overlap |
| 9 PM | 21:00Thu | 20:00Thu | No overlap |
| 10 PM | 22:00Thu | 21:00Thu | No overlap |
| 11 PM | 23:00Thu | 22:00Thu | No overlap |
British Summer Time (BST) sits at UTC+01:00 today, while Greenwich Mean Time (GMT) is at UTC+00:00. The current gap is 1 hour, with BST ahead of GMT. In practical terms, if your morning starts at 9 AM in London, your counterpart in United Kingdom (winter), West Africa, Iceland is seeing 08:00 on their own watch at that exact moment.
BST is the working clock for London, Birmingham and Manchester. BST also refers to Bangladesh Standard Time (Asia/Dhaka). UK usage dominates search volume. GMT covers United Kingdom (winter), West Africa, Iceland. GMT and UTC agree to the second in practice. The UK uses GMT in winter and BST in summer. If your team is split between these two regions, the table above is the quickest way to spot the daily overlap window without doing the offset arithmetic in your head.
Daylight saving matters here. British Summer Time shifts forward an hour on the second Sunday of March (US) or the last Sunday of March (Europe) and back on the first Sunday of November or last Sunday of October. Greenwich Mean Time stays on a fixed offset year-round. The IANA tzdata baked into this page handles every transition automatically, so the table reflects the correct wall-clock times for today's date. For dates further out, use the converter linked above and pick the target date explicitly.
Common scheduling traps are easy to avoid here. Pick a wall-clock time on one side, read the matching wall-clock on the other from the table, and write both into the calendar invite, never just the difference. If the meeting falls in the week of a DST changeover and one of these zones shifts, the absolute clock will drift by an hour from what the recipient expects. The table is computed for today's date, so for a future meeting open the converter linked above and pick the exact date.
One last note for asynchronous teams: business-hour overlap is the wrong metric for handoff workflows. If you operate on a follow-the-sun model, you actually want zero overlap, with one team logging off as the other starts. BST and GMT differ by 1 hours, which is too small for a clean handoff. Pair this with a third zone for genuine 24-hour coverage.
BSTDSTvsUTC
British Summer Time · Coordinated Universal Time
Compare →BSTDSTvsEST
British Summer Time · Eastern Standard Time
Compare →BSTDSTvsEDTDST
British Summer Time · Eastern Daylight Time
Compare →BSTDSTvsCST
British Summer Time · Central Standard Time
Compare →BSTDSTvsPST
British Summer Time · Pacific Standard Time
Compare →BSTDSTvsMST
British Summer Time · Mountain Standard Time
Compare →BSTDSTvsIST
British Summer Time · India Standard Time
Compare →BSTDSTvsJST
British Summer Time · Japan Standard Time
Compare →