Offset
The time difference between India Standard Time and Atlantic Time is 8.5 hours.
India Standard Time (IST) is ahead of Atlantic Time (ADT).
IST: UTC+5:30
ADT: UTC-3
Atlantic Time is currently observing daylight saving time; India Standard Time is not.
When to schedule
Standard business hours (9 AM–5 PM, Mon–Fri) in India Standard Time and Atlantic Time don't overlap on the same weekday. Atlantic Time is 8 hours behind India Standard Time.
With some flexibility, there’s a workable window outside standard hours:
- 4 PM–8 PM in India Standard Time (7 AM–11 AM in Atlantic Time) — suggest 6:00 PM India Standard Time (9:30 AM Atlantic Time).
This means an early start or late finish for one side, but it’s a reasonable slot for a one-off meeting.
This window may shift by an hour during daylight saving time.
Public holidays in 2026
National public holidays can affect availability — a counterpart is likely off work on their own holidays, so it's worth planning meetings and deadlines around them.
Canada
- New Year's DayThu, Jan 1
- Good FridayFri, Apr 3
- Victoria DayMon, May 18
- Canada DayWed, Jul 1
- Labour DayMon, Sep 7
- National Day for Truth and ReconciliationWed, Sep 30
- ThanksgivingMon, Oct 12
- Christmas DayFri, Dec 25
About these zones
India Standard Time is also known as IST. To call India, dial +91.
Atlantic Time is also known as AST, or ADT. To call Canada, dial +1.
Atlantic Time is approximately 7,250 miles northwest of India Standard Time.
Quick reference
Full 24-hour conversion table — tap any time to open it in the converter.
| IST | AST-ATLANTIC | Day |
|---|---|---|
| 12:00 am | 3:30 pm | -1 day |
| 1:00 am | 4:30 pm | -1 day |
| 2:00 am | 5:30 pm | -1 day |
| 3:00 am | 6:30 pm | -1 day |
| 4:00 am | 7:30 pm | -1 day |
| 5:00 am | 8:30 pm | -1 day |
| 6:00 am | 9:30 pm | -1 day |
| 7:00 am | 10:30 pm | -1 day |
| 8:00 am | 11:30 pm | -1 day |
| 9:00 am | 12:30 am | Same day |
| 10:00 am | 1:30 am | Same day |
| 11:00 am | 2:30 am | Same day |
| 12:00 pm | 3:30 am | Same day |
| 1:00 pm | 4:30 am | Same day |
| 2:00 pm | 5:30 am | Same day |
| 3:00 pm | 6:30 am | Same day |
| 4:00 pm | 7:30 am | Same day |
| 5:00 pm | 8:30 am | Same day |
| 6:00 pm | 9:30 am | Same day |
| 7:00 pm | 10:30 am | Same day |
| 8:00 pm | 11:30 am | Same day |
| 9:00 pm | 12:30 pm | Same day |
| 10:00 pm | 1:30 pm | Same day |
| 11:00 pm | 2:30 pm | Same day |
Daylight saving time
Atlantic Time observes daylight saving time; India Standard Time does not. The offset between the two zones changes when Atlantic Time transitions: on Sunday, November 1, 2026, clocks fall back from ADT to AST.
See the daylight saving time page for transition dates across every time zone.
Daylight today
- Sunrise
- 6:01 AM
- Sunset
- 7:15 PM
- Day length
- 13h 14m
- Sunrise
- 5:31 AM
- Sunset
- 8:56 PM
- Day length
- 15h 25m
Daylight overlap: 5h 13m — 2:01 PM–7:15 PM in India Standard Time (5:31 AM–10:45 AM in Atlantic Time). Both locations are in daylight during this window.
Cities in these zones
Cities in India Standard Time
Cities in Atlantic Time
Browse all cities to see the current local time anywhere.
Airports in these zones
Airports in India Standard Time
- BOM
- NMI
- DEL
- BLR
- HYD
- AMD
- MAA
- CCU
- STV
- PNQ
Airports in Atlantic Time
- YHZ
Related conversions
Common conversions
- What is 9:00 am IST in AST-ATLANTIC?
- 9:00 am IST is 12:30 am AST-ATLANTIC.
- What is 12:00 pm IST in AST-ATLANTIC?
- 12:00 pm IST is 3:30 am AST-ATLANTIC.
- What is 12:30 pm IST in AST-ATLANTIC?
- 12:30 pm IST is 4:00 am AST-ATLANTIC.
- What is 2:00 pm IST in AST-ATLANTIC?
- 2:00 pm IST is 5:30 am AST-ATLANTIC.
- What is 5:00 pm IST in AST-ATLANTIC?
- 5:00 pm IST is 8:30 am AST-ATLANTIC.
- What is 11:30 pm IST in AST-ATLANTIC?
- 11:30 pm IST is 3:00 pm AST-ATLANTIC.