Offset
The time difference between Greenwich Mean Time and Calgary is 6 hours.
Greenwich Mean Time (GMT) is ahead of Calgary (MDT).
GMT: UTC
MDT: UTC-6
Calgary is currently observing daylight saving time; Greenwich Mean Time is not.
When to schedule
Business-hours overlap: 4 PM–5 PM in Greenwich Mean Time (9 AM–10 AM in Calgary).
Both teams are in working hours during this window on weekdays.
Suggested time: 4:00 PM Greenwich Mean Time (9:00 AM Calgary).
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.
United Kingdom
- Good FridayFri, Apr 3
- Early May Bank HolidayMon, May 4
- Spring Bank HolidayMon, May 25
- Christmas DayFri, Dec 25
- St. Stephen's DayMon, Dec 28
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
Greenwich Mean Time is also known as GMT, or BST. To call United Kingdom, dial +44.
Calgary uses Mountain Time (MST, or MDT). To call Canada, dial +1.
Calgary is approximately 4,350 miles northwest of Greenwich Mean Time.
Quick reference
Full 24-hour conversion table — tap any time to open it in the converter.
| GMT | Calgary | Day |
|---|---|---|
| 12:00 am | 5:00 pm | -1 day |
| 1:00 am | 6:00 pm | -1 day |
| 2:00 am | 8:00 pm | -1 day |
| 3:00 am | 9:00 pm | -1 day |
| 4:00 am | 10:00 pm | -1 day |
| 5:00 am | 11:00 pm | -1 day |
| 6:00 am | 12:00 am | Same day |
| 7:00 am | 1:00 am | Same day |
| 8:00 am | 2:00 am | Same day |
| 9:00 am | 3:00 am | Same day |
| 10:00 am | 4:00 am | Same day |
| 11:00 am | 5:00 am | Same day |
| 12:00 pm | 6:00 am | Same day |
| 1:00 pm | 7:00 am | Same day |
| 2:00 pm | 8:00 am | Same day |
| 3:00 pm | 9:00 am | Same day |
| 4:00 pm | 10:00 am | Same day |
| 5:00 pm | 11:00 am | Same day |
| 6:00 pm | 12:00 pm | Same day |
| 7:00 pm | 1:00 pm | Same day |
| 8:00 pm | 2:00 pm | Same day |
| 9:00 pm | 3:00 pm | Same day |
| 10:00 pm | 4:00 pm | Same day |
| 11:00 pm | 5:00 pm | Same day |
Daylight saving time
Greenwich Mean Time observes daylight saving time; Calgary does not. The offset between the two zones changes when Greenwich Mean Time transitions: on Sunday, March 28, 2027, clocks spring forward from GMT to BST.
See the daylight saving time page for transition dates across every time zone.
Daylight today
- Sunrise
- 6:42 AM
- Sunset
- 4:49 PM
- Day length
- 10h 7m
- Sunrise
- 8:17 AM
- Sunset
- 6:25 PM
- Day length
- 10h 8m
Daylight overlap: 2h 31m — 2:17 PM–4:49 PM in Greenwich Mean Time (8:17 AM–10:49 AM in Calgary). Both locations are in daylight during this window.
Cities in these zones
Cities in Greenwich Mean Time
Other cities in Mountain Time
Browse all cities to see the current local time anywhere.
Airports in these zones
Airports in Greenwich Mean Time
- LCY
- LGW
- LHR
- LTN
- STN
- BHX
- EMA
- GLA
- PIK
- LBA
Airports in Mountain Time
- YYC
- YEG
Related conversions
Common conversions
- What is 9:00 am GMT in Calgary?
- 9:00 am GMT is 3:00 am Calgary.
- What is 12:00 pm GMT in Calgary?
- 12:00 pm GMT is 6:00 am Calgary.
- What is 12:30 pm GMT in Calgary?
- 12:30 pm GMT is 6:30 am Calgary.
- What is 2:00 pm GMT in Calgary?
- 2:00 pm GMT is 8:00 am Calgary.
- What is 5:00 pm GMT in Calgary?
- 5:00 pm GMT is 11:00 am Calgary.
- What is 11:30 pm GMT in Calgary?
- 11:30 pm GMT is 5:30 pm Calgary.