GMT to MST converter
GMT never changes for daylight saving time, but Mountain Time does, so the gap moves by an hour twice a year. The table below always shows the right one for your date.
Convert Greenwich Mean Time (GMT) to Mountain Standard Time (MST) for any date and time.
Mountain Time is 6 hours behind GMT from March to November, and 7 hours behind the rest of the year.
Right now GMT is UTC+0 and Mountain Time is on MDT (UTC−6). Mountain Time switches back to standard time on 1 November 2026.
US clocks go back on 1 November 2026. From then, MST is 7 hours behind GMT.
9:00 am to 5:00 pm GMT is 3:00 am to 11:00 am MDT.
- 8:00 am GMT is 2:00 am MDT
- 9:00 am GMT is 3:00 am MDT
- 10:00 am GMT is 4:00 am MDT
- 12:00 pm GMT is 6:00 am MDT
- 3:00 pm GMT is 9:00 am MDT
- 5:00 pm GMT is 11:00 am MDT
Hours in Greenwich Mean Time, Fri, Oct 23
Greenwich Mean Time
UTC+0 all year; the UK switches to BST in summer
Fri, Oct 23
GMT · UTC+0ReferenceWorking hoursMountain Time
US & Canada; Arizona stays on MST
Fri, Oct 23
MDT · UTC−6−6h from Greenwich Mean TimeOutside working hours
Best time to meet: 3:00 PM–5:00 PM in Greenwich Mean Time on Fri, Oct 23, when everyone is inside working hours.
Book a meeting in this windowWorking hours: 9:00 AM–5:00 PM, Monday to FridayEveryone at work
GMT to MST conversion table
Every hour of the day in GMT, converted to MDT. Shaded cells are working hours (9:00 am to 5:00 pm); green rows are working hours in both zones.
| GMT | MDTUntil 1 November 2026; From 14 March 2027 | MST1 November 2026 to 14 March 2027 |
|---|---|---|
| 12:00 am GMT | 6:00 pm MDT(day before) | 5:00 pm MST(day before) |
| 1:00 am GMT | 7:00 pm MDT(day before) | 6:00 pm MST(day before) |
| 2:00 am GMT | 8:00 pm MDT(day before) | 7:00 pm MST(day before) |
| 3:00 am GMT | 9:00 pm MDT(day before) | 8:00 pm MST(day before) |
| 4:00 am GMT | 10:00 pm MDT(day before) | 9:00 pm MST(day before) |
| 5:00 am GMT | 11:00 pm MDT(day before) | 10:00 pm MST(day before) |
| 6:00 am GMT | 12:00 am MDT | 11:00 pm MST(day before) |
| 7:00 am GMT | 1:00 am MDT | 12:00 am MST |
| 8:00 am GMT | 2:00 am MDT | 1:00 am MST |
| 9:00 am GMT | 3:00 am MDT | 2:00 am MST |
| 10:00 am GMT | 4:00 am MDT | 3:00 am MST |
| 11:00 am GMT | 5:00 am MDT | 4:00 am MST |
| 12:00 pm GMT | 6:00 am MDT | 5:00 am MST |
| 1:00 pm GMT | 7:00 am MDT | 6:00 am MST |
| 2:00 pm GMT | 8:00 am MDT | 7:00 am MST |
| 3:00 pm GMT | 9:00 am MDT | 8:00 am MST |
| 4:00 pm GMT | 10:00 am MDT | 9:00 am MST |
| 5:00 pm GMT | 11:00 am MDT | 10:00 am MST |
| 6:00 pm GMT | 12:00 pm MDT | 11:00 am MST |
| 7:00 pm GMT | 1:00 pm MDT | 12:00 pm MST |
| 8:00 pm GMT | 2:00 pm MDT | 1:00 pm MST |
| 9:00 pm GMT | 3:00 pm MDT | 2:00 pm MST |
| 10:00 pm GMT | 4:00 pm MDT | 3:00 pm MST |
| 11:00 pm GMT | 5:00 pm MDT | 4:00 pm MST |
Best times to meet
Your working hours overlap for 2 hours, from 3:00 pm GMT (9:00 am MDT) to 5:00 pm GMT (11:00 am MDT). That's the best window for a meeting.
About these time zones
GMT: Greenwich Mean Time
Greenwich Mean Time is UTC+0.
The same time as UTC. The UK, Ireland and Portugal use GMT in winter, then switch to summer time (BST in the UK) from late March to late October. Iceland and much of West Africa stay on GMT all year.
MST: Mountain Standard Time
Mountain Standard Time is UTC−7. MST is also used for Malaysia Standard Time (UTC+8). This page converts US Mountain Time.
Colorado, Utah, New Mexico, Wyoming, Montana and southern Idaho, plus Alberta in Canada. Most of Arizona stays on MST all year (the Navajo Nation follows daylight saving time). MT is the short form for the whole zone.
Most places on Mountain Time are on MDT (UTC−6) right now, not MST. People still say "MST" all year, so the times on this page follow the clocks and show MDT until 1 November 2026.
How the difference changes
Right now MDT is 6 hours behind GMT. From 1 November 2026, when US clocks go back, the difference becomes 7 hours. From 14 March 2027, when US clocks go forward, the difference becomes 6 hours.