MST — Mountain Standard Time
MST is Mountain Standard Time, 7 hours behind UTC. It is a fixed offset: unlike a time zone, it does not change with the season — the zones that use it switch to a different abbreviation instead.
Current time in MST
00:46
Sunday, 2 August 2026
MST = UTC-7 · 7 hours behind UTC
Shown for 2 Aug 2026 07:46 UTC. The clock goes live as soon as scripts load.
UTC offset
UTC-7
Type
Standard time
Seasonal counterpart
MDT
The letters the same zones use for the other half of the year
Meanings
1
Unambiguous
Is MST in force right now?
A zone only carries this abbreviation for part of the year. This is which of them were on it at 2 Aug 2026 07:46 UTC; the list is re-derived against your own clock when scripts load.
On MST now
- America/Phoenix — Phoenix
Using a different abbreviation
- America/Denver — on MDT (UTC-6)
- America/Edmonton — on MDT (UTC-6)
- America/Boise — on MDT (UTC-6)
MST alternates with MDT across the year.
Writing “MST” for a date in the other half of the year is the most common time zone mistake in meeting invitations.
Convert MST to other time zones
City clocks reflect whatever their zone is doing; where a city observes daylight saving time, its difference from MST changes twice a year. Use the time zone converter for a specific date.
Time zones and cities that use MST
Mountain Standard Time · UTC-7
Why MST is not an identifier
MST is shorthand, not a standard. There is no registry of time zone abbreviations, no authority that assigns them, and nothing preventing two regions from adopting the same three letters — which is what makes codes like IST and CST unusable without context.
For anything a machine will read — a calendar invitation, a database column, an API response — use the IANA identifier of the zone (America/Denver, for example) or an explicit UTC offset alongside the date. The identifier survives a change in the law; MST and its 7 hours offset do not.
Abbreviations on the same clock
Frequently asked questions
What does MST stand for?
MST stands for Mountain Standard Time. It is 7 hours behind UTC, written UTC-7.
What is MST in UTC?
MST is UTC-7. To convert an MST time to UTC, add 7 hours.
What is the difference between MST and MDT?
MST is the standard-time form; MDT is what those same zones use during daylight saving time, one hour ahead. A summer date written "MST" is usually a mistake for MDT.
Which time zone should I use instead of MST?
Use an IANA identifier — America/Denver, America/Phoenix and America/Edmonton and 1 more for Mountain Standard Time — or state the UTC offset with the date. Abbreviations are not identifiers: they are not unique, they are not registered anywhere, and half of them change with the season. Calendar software resolves this automatically when you pick a city rather than typing letters.