GMT vs BST: what’s the difference?
GMT and BST are both UK time — just in different seasons. GMT is winter time (UTC+0); BST is summer time (UTC+1), one hour ahead.
| GMT | BST | |
|---|---|---|
| Full name | Greenwich Mean Time | British Summer Time |
| UTC offset | UTC+0 | UTC+1 |
| In force | Last Sun Oct → last Sun Mar (winter) | Last Sun Mar → last Sun Oct (summer) |
| Daylight | Lighter mornings | Lighter evenings |
Is the UK on GMT or BST now?
Direct answer. The UK is on BST (UTC+1) from the last Sunday of March to the last Sunday of October, and on GMT (UTC+0) the rest of the year.
People often say the UK “is on GMT”, but that is only true in winter. For about seven months of the year the correct offset is UTC+1, not UTC+0 — which matters a lot when arranging international calls or travel.
Key fact: For roughly seven months a year the UK is on BST (UTC+1), not GMT.
Related
FAQ
Is GMT the same as BST?
No. GMT (UTC+0) is the UK’s winter time. BST (UTC+1) is the UK’s summer time and is one hour ahead of GMT. They are the same clock shifted by an hour.
Is London on GMT all year?
No — this is a common mistake. London (and the whole UK) is on GMT only in winter. From the last Sunday of March to the last Sunday of October it is on BST, one hour ahead.
Is BST the same as UTC+1?
Yes. British Summer Time is exactly UTC+1. Greenwich Mean Time is UTC+0.