MST to GMT Time Converter
GMT is 7 hours ahead of MST. The US Mountain states are currently on MDT (UTC-6:00), and The UK and Ireland are currently on BST (UTC+1:00).
Best Time to Call Between MST and GMT
Both zones are inside normal business hours between 9:00 AM and 10:00 AM MST — that's 4:00 PM to 5:00 PM GMT. That's a 1-hour window.
both at work MST only GMT only neither — hours along the strip are MST.
Common Times Converted
MST on the left, GMT on the right.
MST to GMT: Full 24-Hour Conversion Table
Shaded rows are working hours; the darker shade marks the hours when both zones are at work.
| MST | GMT | Working hours |
|---|---|---|
| 12:00 AM | 7:00 AM | — |
| 1:00 AM | 8:00 AM | — |
| 2:00 AM | 9:00 AM | GMT only |
| 3:00 AM | 10:00 AM | GMT only |
| 4:00 AM | 11:00 AM | GMT only |
| 5:00 AM | 12:00 PM | GMT only |
| 6:00 AM | 1:00 PM | GMT only |
| 7:00 AM | 2:00 PM | GMT only |
| 8:00 AM | 3:00 PM | GMT only |
| 9:00 AM | 4:00 PM | Both zones |
| 10:00 AM | 5:00 PM | MST only |
| 11:00 AM | 6:00 PM | MST only |
| 12:00 PM | 7:00 PM | MST only |
| 1:00 PM | 8:00 PM | MST only |
| 2:00 PM | 9:00 PM | MST only |
| 3:00 PM | 10:00 PM | MST only |
| 4:00 PM | 11:00 PM | MST only |
| 5:00 PM | 12:00 AM next day | — |
| 6:00 PM | 1:00 AM next day | — |
| 7:00 PM | 2:00 AM next day | — |
| 8:00 PM | 3:00 AM next day | — |
| 9:00 PM | 4:00 AM next day | — |
| 10:00 PM | 5:00 AM next day | — |
| 11:00 PM | 6:00 AM next day | — |
What MST and GMT Actually Are
MST — Mountain Standard Time
Denver, Salt Lake City, Calgary — and Phoenix year-round. Standing at UTC-7:00 as written, and the region does change its clocks, so its live offset moves by an hour twice a year. The next change is on Sunday, November 1, 2026, to MST. Arizona stays on MST all year, so Phoenix and Denver are an hour apart for eight months and identical for four.
Arizona has stayed on MST year-round since 1968 — the Navajo Nation within it does observe daylight saving, making the state a patchwork.
GMT — Greenwich Mean Time
The UK and Ireland in winter, plus Iceland, Portugal and much of West Africa. Standing at UTC as written, and the region does change its clocks, so its live offset moves by an hour twice a year. The next change is on Sunday, October 25, 2026, to GMT. Often used loosely as a synonym for UTC. They differ by less than a second, so for scheduling they are interchangeable.
Britain ran an experiment from 1968 to 1971 on permanent UTC+1, abandoning GMT entirely. It was scrapped after complaints about dark winter mornings in Scotland.
What This Means in Practice
Both sides change clocks, on different dates
Both regions observe daylight saving but do not switch on the same day, so for a week or two each spring and fall the gap between them is an hour different from the rest of the year. Those short windows are where recurring invitations quietly break.
Major Cities in Each Zone
Cities on MST
Cities on GMT
Frequently Asked Questions
What is the time difference between MST and GMT?
GMT is 7 hours ahead of MST.
What is 9:00 AM MST in GMT?
9:00 AM MST is 4:00 PM GMT.
What are the best hours to schedule a call between MST and GMT?
Between 9:00 AM and 10:00 AM MST, which is 4:00 PM to 5:00 PM GMT. Both sides are inside normal business hours through that window.
Does the difference between MST and GMT change during the year?
Yes. Both regions observe daylight saving, and they do not switch on the same dates, so the gap shifts by an hour at least twice a year. The next clock change is on Sunday, November 1, 2026.
Does MST always mean Mountain Standard Time?
Arizona stays on MST all year, so Phoenix and Denver are an hour apart for eight months and identical for four.
Does GMT always mean Greenwich Mean Time?
Often used loosely as a synonym for UTC. They differ by less than a second, so for scheduling they are interchangeable.