What Is Mountain Standard Time?
It covers all or parts of 13 states in the US and five provinces or territories in Canada.
The MST time zone is the least populated time zone in the USA. It spans from northern Canada to Mexico near the equator.
Mountain Standard Time Zone
Mountain Standard Time (MST) is a standard time zone in use from the first Sunday in November to the second Sunday in March—when Daylight Saving Time (DST) is not in effect. Mountain Daylight Time (MDT) is used during the remainder of the year.
MST Is the Mountain Time Zone
In everyday usage, MST is often referred to as Mountain Time (MT) or the Mountain Time Zone. This can add a bit of confusion as the term Mountain Time does not differentiate between standard time and Daylight Saving Time, so Mountain Time switches between MST and MDT in areas that use DST during part of the year.
Converting Mountain Time to Other US Time Zones
- Mountain Standard Time (MST) is 2 hours behind Eastern Standard Time (EST).
To convert MST to EST, you have to add two hours.
- Mountain Standard Time (MST) is 1 hour behind Central Standard Time (CST).
To convert MST to CST, you have to add one hour.
- Mountain Standard Time (MST) is 1 hour ahead of Pacific Standard Time (PST).
To convert MST to PST, you have to subtract one hour.
Where and When is MST Observed?
US states using MST in the winter and MDT in the summer:
- Arizona - Navajo Nation only
- Idaho - most of the state except western counties
Benewah, Bonner, Boundary, Clearwater, Kootenai, Latah, Lewis, Nez Perce, Shoshone and north part of Idaho
- Kansas - some western counties only
Greeley, Hamilton, Sherman and Wallace
- Nebraska - western counties
Arthur, Banner, Box Butte, Chase, Cheyenne, Dawes, Deuel, Dundy, Garden, Grant, Hooker, Keith, Kimball, Morrill, Perkins, Scotts Bluff, Sheridan, and Sioux and the western part of Cherry
- New Mexico
- North Dakota - South-Western parts
counties of Adams, Billings, Bowman, Golden Valley, Grant, Hettinger, Mercer, Slope and Stark, and southern parts of Dunn and McKenzie, most of Morton and Sioux counties
- Oregon - parts of Malheur county only
- South Dakota - western counties
Bennett, Butte, Corson, Custer, Dewey, Fall River, Haakon, Harding, Jackson, Lawrence, Meade, Pennington, Perkins, Shannon, and Ziebach, and the western parts of Stanley
- Texas - a few counties in west
El Paso and Hudspeth and part of Culberson
Canadian provinces/territories using MST in the winter and MDT in the summer:
- British Columbia - a few eastern communities
Cranbrook, Golden, Invermere
- Northwest Territories
- Nunavut - Kugluktuk, Cambridge Bay only (Other parts use EST/EDT or EST only)
- Saskatchewan - only Lloydminster
Mexican states using MST in the winter and MDT in the summer:
Mexican states using MST all year:
US states using MST all year:
except Navajo Nation
Canadian provinces/territories using MST all year:
Other Time Zones in UTC -7
Some time zones exist that have the same offset as MST, but can be found under a different name: