4am GMT is 10:00 pm MST the previous day
4am GMT is 10:00 pm MDT in Mountain Time, on the previous day. MST is 6 hours behind GMT today, and that gap changes during the year, so this is recomputed rather than assumed.
What time is 4am GMT in MST?
It is 10:00 pm. Mountain is 6 hours behind GMT, so you subtract 6 hours from 4:00 am and the result lands on the previous day. 4am is the small hours in GMT, the deadest part of the night, while 10:00 pm is late evening in Mountain, the wind-down before midnight.
The 12 hour clock reuses every number twice, so 4am and 4pm differ only by the meridiem. Converting 4am GMT gives 10:00 pm MST; converting 4pm GMT gives 10:00 am MST. Losing the am or pm loses half the answer.
4am GMT to MST in the hours either side
The four hours before and after 4am, in case the meeting moves. Note that the calendar date does not stay put across this window: it changes partway through, which is exactly where scheduling mistakes come from.
| GMT | MST | MST date | Working hours |
|---|---|---|---|
| 12:00 am | 6:00 pm | the previous day | neither |
| 1:00 am | 7:00 pm | the previous day | neither |
| 2:00 am | 8:00 pm | the previous day | neither |
| 3:00 am | 9:00 pm | the previous day | neither |
| 4:00 am (this page) | 10:00 pm | the previous day | neither |
| 5:00 am | 11:00 pm | the previous day | neither |
| 6:00 am | 12:00 am | same day | neither |
| 7:00 am | 1:00 am | same day | neither |
| 8:00 am | 2:00 am | same day | neither |
Is 4am GMT a good time to call MST?
No. 10:00 pm in Mountain is late evening, the wind-down before midnight. Nobody is taking that call. The zones are 6 hours apart, so the nearest sensible slot is a different hour entirely.
Does daylight saving change 4am GMT to MST?
Yes. Sampled at 4am on every day of 2026, the gap takes 2 different values. Today it is 6 hours, which is why the answer above is dated rather than fixed.
Greenwich Mean Time does not move its clocks at all, so its UTC+0 offset holds every day of the year.
Mountain Time is currently on MDT and changes next on Sunday, November 1, 2026, when the clock falls back from 1:59 am to 1:00 am and the offset moves from UTC-6 to UTC-7.
4am MST to GMT, the other way round
Running the question the other way is a different conversion, not a mirror image, because the two zones can be in different daylight saving states on the same date. 4am MST is 10:00 am GMT, which is a different reading from the answer above, because the two directions are separate questions. One wrinkle worth knowing: MST and MDT are two names for the same zone, not two zones. Mountain Time reads MST in winter and MDT in summer. When somebody types "gmt to mst" they nearly always mean the zone rather than the literal winter offset, so this page resolves GMT to Etc/GMT and MST to America/Denver and applies whichever offset is genuinely in force on the day.
Questions
- What is 4am GMT in MST?
- 10:00 pm MST, the previous day.
- Does 4am GMT cross into another date in MST?
- Yes. It lands on Thursday, September 24, 2026, the previous day.
- Is 4am GMT always 10pm MST?
- No. The gap moves during the year, between 6 hours and 7 hours. Today it is 6 hours.
- How is 4am GMT written in 24 hour time?
- 04:00, and the answer in MST is 22:00.
- Can I call Mountain at that hour?
- 10:00 pm is outside the 9 to 5 working day in Mountain.
Other hours on this pair
GMT to MST full conversion table · MST to GMT · 4am MST to GMT · All timezone conversions
12 and 24 hour converter · 8 hours from now · Today · Day counter