Offset
The time difference between Belfast and Mountain Time is 7 hours.
Belfast (BST) is ahead of Mountain Time (MDT).
BST: UTC+1
MDT: UTC-6
Both zones are currently observing daylight saving time.
When to schedule
Business-hours overlap: 4 PM–5 PM in Belfast (9 AM–10 AM in Mountain Time).
Both teams are in working hours during this window on weekdays.
Suggested time: 4:00 PM Belfast (9:00 AM Mountain Time).
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
United States
- New Year's DayThu, Jan 1
- Martin Luther King, Jr. DayMon, Jan 19
- Presidents DayMon, Feb 16
- Memorial DayMon, May 25
- Juneteenth National Independence DayFri, Jun 19
- Independence DayFri, Jul 3
- Labour DayMon, Sep 7
- Columbus DayMon, Oct 12
- Veterans DayWed, Nov 11
- Thanksgiving DayThu, Nov 26
- Christmas DayFri, Dec 25
About these zones
Belfast uses Greenwich Mean Time (GMT, or BST). To call United Kingdom, dial +44.
Mountain Time is also known as MST, or MDT. To call United States, dial +1.
Mountain Time is approximately 4,350 miles northwest of Belfast.
Quick reference
Full 24-hour conversion table — tap any time to open it in the converter.
| Belfast | MST | Day |
|---|---|---|
| 12:00 am | 5:00 pm | -1 day |
| 1:00 am | 6:00 pm | -1 day |
| 2:00 am | 7:00 pm | -1 day |
| 3:00 am | 8:00 pm | -1 day |
| 4:00 am | 9:00 pm | -1 day |
| 5:00 am | 10:00 pm | -1 day |
| 6:00 am | 11:00 pm | -1 day |
| 7:00 am | 12:00 am | Same day |
| 8:00 am | 1:00 am | Same day |
| 9:00 am | 2:00 am | Same day |
| 10:00 am | 3:00 am | Same day |
| 11:00 am | 4:00 am | Same day |
| 12:00 pm | 5:00 am | Same day |
| 1:00 pm | 6:00 am | Same day |
| 2:00 pm | 7:00 am | Same day |
| 3:00 pm | 8:00 am | Same day |
| 4:00 pm | 9:00 am | Same day |
| 5:00 pm | 10:00 am | Same day |
| 6:00 pm | 11:00 am | Same day |
| 7:00 pm | 12:00 pm | Same day |
| 8:00 pm | 1:00 pm | Same day |
| 9:00 pm | 2:00 pm | Same day |
| 10:00 pm | 3:00 pm | Same day |
| 11:00 pm | 4:00 pm | Same day |
Daylight saving time
Both zones observe daylight saving time, but they transition on different dates.
Belfast: next transition on Sunday, October 25, 2026.
Mountain Time: next transition on Sunday, November 1, 2026.
For approximately 7 days between transitions, the offset between Belfast and Mountain Time differs from its typical value. Recurring meetings during this window will shift by one hour.
See the daylight saving time page for transition dates across every time zone.
Daylight today
- Sunrise
- 4:50 AM
- Sunset
- 9:57 PM
- Day length
- 17h 6m
- Sunrise
- 5:33 AM
- Sunset
- 8:26 PM
- Day length
- 14h 53m
Cities in these zones
Other cities in Greenwich Mean Time
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
- BJC
- DEN
- OGD
- SLC
Related conversions
Common conversions
- What is 9:00 am Belfast in MST?
- 9:00 am Belfast is 2:00 am MST.
- What is 12:00 pm Belfast in MST?
- 12:00 pm Belfast is 5:00 am MST.
- What is 12:30 pm Belfast in MST?
- 12:30 pm Belfast is 5:30 am MST.
- What is 2:00 pm Belfast in MST?
- 2:00 pm Belfast is 7:00 am MST.
- What is 5:00 pm Belfast in MST?
- 5:00 pm Belfast is 10:00 am MST.
- What is 11:30 pm Belfast in MST?
- 11:30 pm Belfast is 4:30 pm MST.