Simple rule
If you write GMT for a summer meeting, double-check the date.
BST is British Summer Time. GMT is Greenwich Mean Time. The UK uses GMT in winter and BST in summer. Short version, but very worth remembering.
When the audience is broad, saying London time or UK time is often easier than making everyone decode BST vs GMT from memory.
| Term | Meaning | When it applies |
|---|---|---|
| GMT | Greenwich Mean Time | UK winter time |
| BST | British Summer Time | UK summer time during DST |
| Safer label | UK time / London time | When clarity matters more than jargon |
If you write GMT for a summer meeting, double-check the date.
London time is often the simplest wording for non-technical audiences.
For engineering work, Europe/London is the cleanest unambiguous label.