BST to GMT time conversion
GMT is 1 hour behind BST.
Time difference with your location
BST is 1 hour ahead of UTC. Compare with your local time →
Choose a date and time
Choose the local time in BST to convert it to GMT on that date.
Skipped clock-change times are unavailable; a repeated time uses its first occurrence.
24-hour conversion chart · BST → GMT
This table converts each hour in BST to GMT on 2026-10-21.
- Working hours
- Outside working hours
- Night hours
| BST | GMT | Shared working hours |
|---|---|---|
| 00:0012:00 AM | 23:0011:00 PM -1 day | |
| 01:001:00 AM | 00:0012:00 AM | |
| 02:002:00 AM | 01:001:00 AM | |
| 03:003:00 AM | 02:002:00 AM | |
| 04:004:00 AM | 03:003:00 AM | |
| 05:005:00 AM | 04:004:00 AM | |
| 06:006:00 AM | 05:005:00 AM | |
| 07:007:00 AM | 06:006:00 AM | |
| 08:008:00 AM | 07:007:00 AM | |
| 09:009:00 AM | 08:008:00 AM | ✓ |
| 10:0010:00 AM | 09:009:00 AM | ✓ |
| 11:0011:00 AM | 10:0010:00 AM | ✓ |
| 12:0012:00 PM | 11:0011:00 AM | ✓ |
| 13:001:00 PM | 12:0012:00 PM | ✓ |
| 14:002:00 PM | 13:001:00 PM | ✓ |
| 15:003:00 PM | 14:002:00 PM | ✓ |
| 16:004:00 PM | 15:003:00 PM | ✓ |
| 17:005:00 PM | 16:004:00 PM | ✓ |
| 18:006:00 PM | 17:005:00 PM | |
| 19:007:00 PM | 18:006:00 PM | |
| 20:008:00 PM | 19:007:00 PM | |
| 21:009:00 PM | 20:008:00 PM | |
| 22:0010:00 PM | 21:009:00 PM | |
| 23:0011:00 PM | 22:0010:00 PM |
Quick conversion examples
These examples use BST (UTC+1) and GMT (UTC+0); choosing a date applies the local clock changes.
Conversion formula: GMT = BST − 1h · UTC = GMT · UTC = BST − 1h.
| BST | GMT |
|---|---|
| 6:00 AM BST | = 5:00 AM GMT |
| 7:00 AM BST | = 6:00 AM GMT |
| 8:00 AM BST | = 7:00 AM GMT |
| 9:00 AM BST | = 8:00 AM GMT |
| 10:00 AM BST | = 9:00 AM GMT |
| 12:00 PM BST | = 11:00 AM GMT |
| 3:00 PM BST | = 2:00 PM GMT |
| 5:00 PM BST | = 4:00 PM GMT |
| 6:00 PM BST | = 5:00 PM GMT |
| 8:00 PM BST | = 7:00 PM GMT |
Overlapping meeting hours
The 08:00–18:00 working day in BST and GMT overlaps for 9 hours on 2026-10-21.
- Shared working hours
- 09:00–18:00 BST · 08:00–17:00 GMT
Clock changes on both sides, 2026–2028
BST and GMT have the following local clock changes in 2026–2028; all times in the table are local to that side.
| Year | BST | GMT |
|---|---|---|
| 2026 | · 01:00 → 02:00 · 02:00 → 01:00 | No clock changes; UTC+0 all year. |
| 2027 | · 01:00 → 02:00 · 02:00 → 01:00 | No clock changes; UTC+0 all year. |
| 2028 | · 01:00 → 02:00 · 02:00 → 01:00 | No clock changes; UTC+0 all year. |
At the start of 2026, UTC has the same time as GMT. The difference changes during the following periods.
- From 2026-03-29 02:00 BST until 2026-10-25 01:00 GMT, UTC is 1 hour behind BST.
- From 2027-03-28 02:00 BST until 2027-10-31 01:00 GMT, UTC is 1 hour behind BST.
- From 2028-03-26 02:00 BST until 2028-10-29 01:00 GMT, UTC is 1 hour behind BST.
Frequently asked questions
What time is 9 AM BST in GMT?
9:00 AM BST = 8:00 AM GMT, using UTC+1 and UTC+0. Choose a date above for the seasonal local time.
Does the time difference between BST and GMT change during the year?
Yes. During 2026–2028: GMT is 1 hour behind BST; GMT has the same time as BST. The clock-change table gives the dates for both sides.
How do I tell whether it is day or night in GMT?
Read the UTC clock above: this guide counts 06:00–18:00 local time as daytime and the rest as nighttime, without using sunrise and sunset.
What is the best time to call between BST and GMT?
The shared 08:00–18:00 working window is 09:00–18:00 UTC+1 / 08:00–17:00 UTC, a total of 9 hours.
What is the time difference between BST and GMT now?
Right now, UTC is 1 hour behind UTC+1. Conversion formula: GMT = BST − 1h · UTC = GMT · UTC = BST − 1h.