IST to London Time Converter
Convert India Standard Time (IST) to London, United Kingdom. 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 London
IST is 4 hours and 30 minutes ahead of London.
Quick answer. London is 5 hours and 30 minutes behind IST for part of the year and 4 hours and 30 minutes behind for the rest, because London observes daylight saving time and the other side does not. The gap is 5 hours and 30 minutes during London's standard-time months and 4 hours and 30 minutes during daylight time, so always convert against a specific date.
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.
London, United Kingdom
GMT UTC+0:00 BST UTC+1:00 Observes DST
London and the rest of the United Kingdom.
- ↑ March 29, 2026 clocks forward at 2:00 AM · UTC+0:00 → UTC+1:00
- ↓ October 25, 2026 clocks back at 1:00 AM · UTC+1:00 → UTC+0:00
IST to London conversion table
Every hour of the day for 2026. Because London changes clocks twice a year, these values shift by an hour across the daylight saving boundary — use the date picker above for a specific day.
| IST | London | 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 London.
Popular conversion times
| IST | London |
|---|---|
| 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 London, 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 London , 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 (London) | 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 London 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 London
- 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 London 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.
Frequently asked questions
What is the time difference between IST and London?
It depends on the date. London is 5 hours and 30 minutes behind IST in January and 4 hours and 30 minutes behind in July, because London changes clocks for daylight saving time. Use the converter above with the date you actually need.
What time is 9 AM IST in London?
9:00 AM IST is 3:30 AM in London during GMT, and 4:30 AM during BST. The table on this page lists all 24 hours for the date you pick.
What is the best time for a meeting between IST and London?
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 London. For a recurring invite, 2 PM IST / 9:30 AM London 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 London comes entirely from the other side.
When do the clocks change in London?
In 2026, clocks in London go forward on March 29, 2026 and back on October 25, 2026. Between those dates the gap from India is 4 hours and 30 minutes; outside them it is 5 hours and 30 minutes.
Why does the IST–London difference change during the year?
Because London switches between GMT (UTC+0:00) and BST (UTC+1:00) for daylight saving, while the other side does not move. A converter that assumes one fixed gap will be an hour wrong for roughly half the year.
How many hours a week do IST and London actually overlap?
20 hours across the week, spread over 5 working days. 2 PM IST (9:30 AM London) 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 London 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 London 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 London?
Yes. IST runs ahead of London — by 4 hours and 30 minutes or 5 hours and 30 minutes depending on the season, so a working morning in IST lands the previous evening or night in London.
Converting the other way
Looking up times starting from London? Use the London to IST converter, which leads with London as the starting point and is written for that reader.
Other cities in United Kingdom
- IST to Birmingham · United Kingdom
Related converters
- IST to EST · Eastern Time
- IST to CST · Central Time
- IST to PST · Pacific Time
- IST to UTC · Coordinated Universal Time
- IST to GMT · Greenwich Mean Time
- IST to CET · Central European Time
- IST to GST · Gulf Standard Time
- IST to MST · Mountain Time
All cities in United Kingdom: IST to United Kingdom. Scheduling repeatedly? Best Meeting Times: India and the UK compares several cities at once.