What is IST in BST?
British Time is 4 hours 30 minutes behind
India Standard Time is on UTC+5:30 and British Time is on UTC+1:00 right now. British Time is on daylight saving, so its clocks read BST. The gap changes during the year — see below.
- Time in New Delhi
- 7:44 am
- Time in London
- 3:14 am
- Difference
- −4:30 h
- Next clock change
- October 25, 2026
Convert a time
BST — British Time
2:30 am
Wed
When the difference changes
India Standard Time and British Time do not change their clocks on the same dates, so the gap between them is not the same all year. Most converters show only today’s figure. These are the periods ahead:
- Now – October 25, 2026British Time is 4 hours 30 minutes behind
- October 25, 2026 – March 28, 2027British Time is 5 hours 30 minutes behind
- March 28, 2027 – onwardsBritish Time is 4 hours 30 minutes behind
Periods shorter than a day are not listed: both zones change at 2am in their own local time, so there are a few hours on each transition date when the gap is briefly something else.
Daylight saving
India Standard Time
India Standard Time stays on IST all year, so its offset from UTC never moves.
British Time
Clocks go back one hour at 2am local time, becoming GMT.
IST to BST conversion table
Every hour of Wednesday, September 23, 2026, converted from India Standard Time to British Time. 5 of the 24 hours fall on a different calendar day in London, which is marked.
- 12:00 am IST
- 7:30 pm BST−1 day
- 1:00 am IST
- 8:30 pm BST−1 day
- 2:00 am IST
- 9:30 pm BST−1 day
- 3:00 am IST
- 10:30 pm BST−1 day
- 4:00 am IST
- 11:30 pm BST−1 day
- 5:00 am IST
- 12:30 am BST
- 6:00 am IST
- 1:30 am BST
- 7:00 am IST
- 2:30 am BST
- 8:00 am IST
- 3:30 am BST
- 9:00 am IST
- 4:30 am BST
- 10:00 am IST
- 5:30 am BST
- 11:00 am IST
- 6:30 am BST
- 12:00 pm IST
- 7:30 am BST
- 1:00 pm IST
- 8:30 am BST
- 2:00 pm IST
- 9:30 am BST
- 3:00 pm IST
- 10:30 am BST
- 4:00 pm IST
- 11:30 am BST
- 5:00 pm IST
- 12:30 pm BST
- 6:00 pm IST
- 1:30 pm BST
- 7:00 pm IST
- 2:30 pm BST
- 8:00 pm IST
- 3:30 pm BST
- 9:00 pm IST
- 4:30 pm BST
- 10:00 pm IST
- 5:30 pm BST
- 11:00 pm IST
- 6:30 pm BST
Scheduling between the two
Working hours overlap from 2:00 pm to 6:00 pm IST, which is 9:30 am to 1:30 pm BST. Anything inside that window falls in the normal working day at both ends.
A note on IST: it can also mean Israel Standard Time (UTC+2) and Irish Standard Time (UTC+1). This page means India Standard Time, which is what almost all searches for IST want.
A note on BST: it can also mean Bangladesh Standard Time (UTC+6). This page means British Summer Time.
India Standard Time (IST) is used in all of India and Sri Lanka, on a single UTC+5:30 offset with no daylight saving
British Time (BST) is used in the whole United Kingdom. In winter the UK is on GMT; from late March to late October it is on BST, an hour ahead.