IST to BST time converter
BST is 4h 30m behind IST. BST is London's summer time; in 2026 it runs Mar 29 to Oct 24. From Oct 25 it's GMT, and the gap becomes 5h 30m. 9:00 AM IST is 4:30 AM BST.
How many hours is BST from IST?
During this season, BST is 4h 30m behind IST.
BST is London's summer time. Outside Mar 29 to Oct 24, London is on GMT and the gap is 5h 30m. For the whole year, see IST to GMT.
When is BST used?
- 2026: Mar 29 to Oct 24
- 2027: Mar 28 to Oct 30
Computed from your browser's time zone database (IANA Europe/London).
What's the best time for a meeting between IST and BST?
1:30 PM to 6:00 PM IST (9:00 AM to 1:30 PM BST) falls inside 9 AM to 6 PM work hours on both sides.
What time is it in BST for each hour in IST?
Every hour in IST while London is on BST (Mar 29 to Oct 24). Green means work hours (9 AM to 6 PM) on both sides.
| IST | BST | Day |
|---|---|---|
| 12:00 AM | 7:30 PM | previous day |
| 1:00 AM | 8:30 PM | previous day |
| 2:00 AM | 9:30 PM | previous day |
| 3:00 AM | 10:30 PM | previous day |
| 4:00 AM | 11:30 PM | previous day |
| 5:00 AM | 12:30 AM | |
| 6:00 AM | 1:30 AM | |
| 7:00 AM | 2:30 AM | |
| 8:00 AM | 3:30 AM | |
| 9:00 AM | 4:30 AM | |
| 10:00 AM | 5:30 AM | |
| 11:00 AM | 6:30 AM | |
| 12:00 PM | 7:30 AM | |
| 1:00 PM | 8:30 AM | |
| 2:00 PM | 9:30 AM | |
| 3:00 PM | 10:30 AM | |
| 4:00 PM | 11:30 AM | |
| 5:00 PM | 12:30 PM | |
| 6:00 PM | 1:30 PM | |
| 7:00 PM | 2:30 PM | |
| 8:00 PM | 3:30 PM | |
| 9:00 PM | 4:30 PM | |
| 10:00 PM | 5:30 PM | |
| 11:00 PM | 6:30 PM |
Questions
BST is 4h 30m behind IST. That's while London is on BST, Mar 29 to Oct 24, 2026. The rest of the year it's GMT and the gap is 5h 30m.
London uses BST from Mar 29 to Oct 24, 2026, then GMT until Mar 27, 2027. BST starts again on Mar 28, 2027. The clocks on this page always use the right one for the date you pick.
They are the same place, London, at different times of year. BST is one hour ahead of GMT. If someone writes GMT in summer, they almost always mean BST.
9:00 AM IST is 4:30 AM BST.
1:30 PM to 6:00 PM IST (9:00 AM to 1:30 PM BST) falls inside 9 AM to 6 PM work hours on both sides.
Drag on the IST clock above to mark when you're free, then tap Copy link or Copy image. The BST clock shows them in their time, and the link opens in their own time zone with no sign-up.
Related conversions
More with IST or BST: EST to IST, PST to IST, CST to IST, UTC to IST, GMT to IST, IST to EDT, EDT to IST, IST to PDT, PDT to IST, IST to CDT, CDT to IST, CET to IST, IST to CET, AEST to IST, SGT to IST, GMT to EST, GST to IST, IST to MST, IST to AEST, IST to SGT, IST to GST, IST to JST, IST to NZT, EST to GMT, PST to GMT, GMT to PST, WAT to GMT, EAT to GMT
How this page is made: every time here is computed from the IANA time zone database for the date shown, the same data your phone clock uses. Checked October 15, 2026. Spot a wrong time? Tell us.