IST to BST Converter
Convert India Standard Time (IST) to British Summer Time (BST). Pick any date — daylight saving is applied from the IANA time zone database, so the answer is right in March and in November.
IST to BST
IST is 4 hours and 30 minutes ahead of BST.
Quick answer. BST is 4 hours and 30 minutes behind IST, and that gap never changes. Neither IST nor BST observes daylight saving time, so the same conversion is correct on every date of the year.
Time difference
India Standard Time (IST)
IST UTC+5:30 No DST
Mumbai, Delhi, Bengaluru, Chennai, Kolkata, Hyderabad.
India runs on a single time zone, UTC+5:30, and has not observed daylight saving time since 1945. The half-hour offset is why IST conversions rarely land on a round hour.
British Summer Time (BST)
BST UTC+1:00 No DST
London, Manchester, Birmingham, Edinburgh, Glasgow.
BST is UTC+1:00 and runs from the last Sunday in March to the last Sunday in October. Outside that window the UK is on GMT, and the gap from India grows by an hour.
IST to BST conversion table
Every hour of the day for 2026. Neither side observes daylight saving, so this table is correct on every date of the year.
| IST | BST | 24-hour |
|---|---|---|
| 12 AM | 7:30 PM −1 day | 19:30 |
| 1 AM | 8:30 PM −1 day | 20:30 |
| 2 AM | 9:30 PM −1 day | 21:30 |
| 3 AM | 10:30 PM −1 day | 22:30 |
| 4 AM | 11:30 PM −1 day | 23:30 |
| 5 AM | 12:30 AM | 00:30 |
| 6 AM | 1:30 AM | 01:30 |
| 7 AM | 2:30 AM | 02:30 |
| 8 AM | 3:30 AM | 03:30 |
| 9 AM | 4:30 AM | 04:30 |
| 10 AM | 5:30 AM | 05:30 |
| 11 AM | 6:30 AM | 06:30 |
| 12 PM | 7:30 AM | 07:30 |
| 1 PM | 8:30 AM | 08:30 |
| 2 PM | 9:30 AM | 09:30 |
| 3 PM | 10:30 AM | 10:30 |
| 4 PM | 11:30 AM | 11:30 |
| 5 PM | 12:30 PM | 12:30 |
| 6 PM | 1:30 PM | 13:30 |
| 7 PM | 2:30 PM | 14:30 |
| 8 PM | 3:30 PM | 15:30 |
| 9 PM | 4:30 PM | 16:30 |
| 10 PM | 5:30 PM | 17:30 |
| 11 PM | 6:30 PM | 18:30 |
Highlighted rows are the 4 hours where a 9–6 working day in IST overlaps a 9–5 working day in BST.
Popular conversion times
| IST | BST |
|---|---|
| 9 AM IST | 4:30 AM |
| 10 AM IST | 5:30 AM |
| 11 AM IST | 6:30 AM |
| 12 PM IST | 7:30 AM |
| 3 PM IST | 10:30 AM |
| 5 PM IST | 12:30 PM |
| 6 PM IST | 1:30 PM |
| 8 PM IST | 3:30 PM |
Business hours and meeting times
Comparing a 9:00–18:00 working day in IST against 9:00–17:00 in BST, across the whole week — a slot only counts if it lands on a working day at both ends.
Both sides work Monday to Friday, so the working weeks line up and you share 5 days.
Rows are days in IST. Columns are hours of the IST day.
Best recurring slot
2 PM IST = 9:30 AM BST , every shared working day
Across the week that is 20 overlapping working hours . The widest day is Monday, with 4 hours.
| Day | Overlap (IST) | Local (BST) | Hours |
|---|---|---|---|
| Monday | 2 PM – 6 PM | 9:30 AM – 1:30 PM | 4 |
| Tuesday | 2 PM – 6 PM | 9:30 AM – 1:30 PM | 4 |
| Wednesday | 2 PM – 6 PM | 9:30 AM – 1:30 PM | 4 |
| Thursday | 2 PM – 6 PM | 9:30 AM – 1:30 PM | 4 |
| Friday | 2 PM – 6 PM | 9:30 AM – 1:30 PM | 4 |
| Saturday | IST weekend | — | — |
| Sunday | IST weekend | — | — |
Public holidays
A shared working day is only usable if neither side is on holiday — and India and BST build their calendars on different systems, so the days each loses rarely coincide.
Over the next 8 weeks you share 40 working days. 2are lost to a public holiday on one side or the other, leaving 38.
| Date | Who is off | Holiday |
|---|---|---|
| Friday, October 2, 2026 | India | Gandhi Jayanti |
| Tuesday, October 20, 2026 | India | Dussehra (Vijayadashami) |
Next holidays in India
- Friday, October 2, 2026Gandhi Jayantisame date every year
- Tuesday, October 20, 2026Dussehra (Vijayadashami)partialpublished date
- Sunday, November 8, 2026Diwalipublished date
- Monday, November 9, 2026Diwalipublished date
- Friday, December 25, 2026Christmas Daypartialsame date every year
India has three national holidays on which the whole country closes. Everything else is either a central-government gazetted holiday that individual employers choose to observe, or a state holiday. Festival dates follow lunisolar calendars and move every year, so they are listed explicitly rather than derived.
Next holidays in BST
- Monday, November 30, 2026Saint Andrew's Dayregionalpublished date
- Friday, December 25, 2026Christmas Daypublished date
- Monday, December 28, 2026St. Stephen's Day (Boxing Day)published date
- Friday, January 1, 2027New Year's Dayregionalpublished date
- Saturday, January 2, 20272 Januaryregionalpublished date
Public holidays as published by https://date.nager.at, covering 2026–2028. Regional and employer-specific days are not included.
Holiday dates for BST and elsewhere come from a dataset last refreshed on 2026-09-12 (date.nager.at plus curated national calendars). Lunar dates — Eid, Chinese New Year, the Jewish holidays — are predicted and can move by a day once officially announced. Regional, state and employer-specific holidays are not included. Confirm anything you are booking a flight around.
About this conversion
India runs on a single time zone, UTC+5:30, and has not observed daylight saving time since 1945. The half-hour offset is why IST conversions rarely land on a round hour.
BST is UTC+1:00 and runs from the last Sunday in March to the last Sunday in October. Outside that window the UK is on GMT, and the gap from India grows by an hour.
Frequently asked questions
What is the time difference between IST and BST?
BST is 4 hours and 30 minutes behind IST, on every date of the year. Neither side observes daylight saving time.
What time is 9 AM IST in BST?
9:00 AM IST is 4:30 AM in BST, all year round.
What is the best time for a meeting between IST and BST?
Working days overlap for about 4 hours on a typical Monday: 2 PM to 6 PM IST, which is 9:30 AM to 1:30 PM in BST. For a recurring invite, 2 PM IST / 9:30 AM BST is the slot that works on the most days.
Does India observe daylight saving time?
No. India has kept a single UTC+5:30 offset since 1945 and does not use daylight saving time, so IST reads the same on every date of the year. Any change in the gap to BST comes entirely from the other side.
How many hours a week do IST and BST actually overlap?
20 hours across the week, spread over 5 working days. 2 PM IST (9:30 AM BST) is the slot that works on the most days, so it is the one to put in a recurring invite.
Do public holidays in IST and BST line up?
Barely. Over the next eight weeks the two sides share 40 working days, and 2 of those are a public holiday on one side or the other, leaving 38. The next holiday in BST is Saint Andrew's Day on 2026-11-30. Indian, Gulf and Western holiday calendars are built on different systems, so the days each side loses rarely coincide.
Is IST ahead of BST?
Yes. IST runs ahead of BST by 4 hours and 30 minutes, so a working morning in IST lands the previous evening or night in BST.
Converting the other way
Looking up times starting from BST? Use the BST to IST converter, which leads with BST as the starting point and is written for that reader.
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