Convert MST to GMT
See the 7-hour time difference between MST (UTC-7) and GMT (UTC+0), compare hours side by side, and schedule meetings fast.
How to Convert MST to GMT
Open the MST to GMT converter: Go to https://www.xconvert.com/time-converter/mst-to-gmt-converter. The page loads with MST and GMT already set up in the visual comparison grid, which is useful if you are scheduling a support handoff from Phoenix or coordinating with partners, shipping agents, or media teams that work on Greenwich Mean Time.
Add relevant comparison cities: Click + Add City and add cities such as Phoenix, Denver, and London to see how Mountain-region schedules compare with a GMT-based business day. This is especially practical for remote software teams, aviation operations, and international customer support groups that need to compare fixed MST hours with UK or Africa-facing GMT schedules.
Drag to select the meeting window: Click Select, then drag across the MST row to highlight a time range in purple, such as 9:00 AM to 11:00 AM MST. That selection shows immediately as 4:00 PM to 6:00 PM GMT, helping you confirm that a late-morning call in Arizona fits into a late-afternoon slot for teams working on GMT.
Export and share the result: After selecting the range, use the export options shown on the page: ICS download, Google Calendar, Gmail, Copy to clipboard, or Share link. This is useful when you need to send a confirmed meeting block to a distributed team so each person sees the event in local time without manually converting MST to GMT.
Understanding the MST to GMT Time Difference
Mountain Standard Time (MST) is UTC-7, while Greenwich Mean Time (GMT) is UTC+0, so GMT is exactly 7 hours ahead of MST. That means when it is 9:00 AM MST, it is 4:00 PM GMT on the same calendar day. This fixed relationship applies only when you are comparing true MST, not Mountain Daylight Time.
The main source of confusion is daylight saving time in North America. Many places in the Mountain Time region, including Denver, Salt Lake City, Calgary, and Edmonton, do not stay on MST all year; they switch to MDT (UTC-6) during daylight saving time. In the United States and Canada, DST typically begins on the second Sunday in March and ends on the first Sunday in November, so during that period the difference from GMT becomes 6 hours instead of 7.
A key exception is Arizona, where most of the state, including Phoenix, stays on MST year-round and does not observe DST. For that reason, Phoenix remains 7 hours behind GMT in every month, while cities like Denver are 7 hours behind GMT from early November to mid-March and 6 hours behind GMT from mid-March to early November. If you are booking calls for travel, logistics, or cross-border operations, this distinction matters because a recurring meeting can shift by one hour depending on whether the Mountain location observes DST.
Best Times for Calls and Meetings Between MST and GMT
Because GMT is 7 hours ahead of MST, the most practical overlap usually happens during the MST morning and early GMT evening. A standard business day of 9:00 AM to 5:00 PM MST converts to 4:00 PM to 12:00 AM GMT, which means only the earlier part of the MST workday overlaps comfortably with a normal GMT office schedule.
A strong meeting window is 8:00 AM to 10:00 AM MST = 3:00 PM to 5:00 PM GMT. This works well for consulting calls, project updates, and account management because both sides are still inside standard office hours. Another reliable option is 9:00 AM to 11:00 AM MST = 4:00 PM to 6:00 PM GMT, which is often used by SaaS teams, agencies, and operations managers coordinating between Arizona-based staff and UK- or West Africa-based partners using GMT.
If the GMT side can stay slightly later, 11:00 AM MST = 6:00 PM GMT and 12:00 PM MST = 7:00 PM GMT can still work for urgent reviews, legal approvals, or end-of-day reporting. Earlier than 7:00 AM MST = 2:00 PM GMT may be too early for many Mountain-region teams, while later than 1:00 PM MST = 8:00 PM GMT becomes inconvenient for most GMT-based professionals. For recurring meetings, the best compromise is usually 9:00 AM MST / 4:00 PM GMT, especially when one side is in Arizona and remains on MST throughout the year.
Frequently Asked Questions
What is the time difference between MST and GMT?
GMT is 7 hours ahead of MST when you are comparing true Mountain Standard Time to Greenwich Mean Time. Since MST is UTC-7 and GMT is UTC+0, you add 7 hours to convert MST to GMT. For example, 1:00 PM MST becomes 8:00 PM GMT.
When is 9 AM MST in GMT?
9:00 AM MST is 4:00 PM GMT on the same day. This is one of the most common conversion checks for business meetings because it places a Mountain morning call into a late-afternoon GMT slot that is still workable for many offices.
Does the difference between MST and GMT change during daylight saving time?
It can change depending on the location you mean by “Mountain time.” If the place observes daylight saving time, it switches from MST (UTC-7) to MDT (UTC-6) from the second Sunday in March to the first Sunday in November, making the difference from GMT 6 hours during that period. If the location is Phoenix, Arizona, the area stays on MST year-round, so the difference remains 7 hours all year.
What is the best meeting time between MST and GMT?
The best shared window is usually 8:00 AM to 11:00 AM MST, which converts to 3:00 PM to 6:00 PM GMT. That range keeps the meeting inside normal working hours for Mountain-based teams and still manageable for GMT-based teams in London-adjacent winter schedules, Iceland, Ghana, or other GMT-using locations.
How do I convert MST to GMT quickly?
The fastest method is to add 7 hours to the MST time. So 6:00 AM MST = 1:00 PM GMT, 10:00 AM MST = 5:00 PM GMT, and 3:00 PM MST = 10:00 PM GMT. On xconvert’s visual grid, you can drag over the MST timeline and instantly see the matching GMT hours without doing mental math.
Why do some Mountain Time cities not match MST all year?
Many cities in the Mountain region use Mountain Daylight Time in spring and summer instead of MST. For example, Denver moves to UTC-6 during DST, while Phoenix generally stays at UTC-7 all year. That is why the same “Mountain” label can produce different GMT conversions depending on the city and month.
Is GMT the same as UK time?
Not all year. The UK uses GMT in winter, but during daylight saving time it switches to British Summer Time (BST), UTC+1, from the last Sunday in March to the last Sunday in October. So if you are scheduling with London in summer, you may need to compare MST with BST, not GMT, which changes the difference by another hour.