Mountain Time: MST and MDT
Mountain Standard Time (MST) is UTC−7, 2 hours behind Eastern Time and 1 hour ahead of Pacific. From the second Sunday in March to the first Sunday in November the zone uses Mountain Daylight Time (MDT), UTC−6, except Arizona, which stays on MST all year. Denver, Salt Lake City, Albuquerque, Boise and Phoenix are on Mountain Time.
By Asier Fernández ·
Right now in Denver: --:--:--
Right now in Phoenix: --:--:--
MST or MDT? The change dates
| Year | Daylight time starts (2 a.m.) | Standard time returns (2 a.m.) |
|---|---|---|
| 2026 | Sunday, March 8 | Sunday, November 1 |
| 2027 | Sunday, March 14 | Sunday, November 7 |
| 2028 | Sunday, March 12 | Sunday, November 5 |
Set by federal law (15 U.S.C. 260a). In 2026 Denver, Salt Lake City and Boise return to MST on Sunday, November 1. Phoenix does not change.
Convert Mountain Time
Is Arizona on Mountain Time?
Yes, on Mountain Standard Time all year. Arizona law sets the state's time as “standard mountain time” and rejects daylight saving time (A.R.S. 1-242); federal law lets a state do this if the whole state stays on standard time (15 U.S.C. 260a). So from March to November, Phoenix shows the same time as Los Angeles and one hour less than Denver. From November to March it matches Denver.
| When it is noon in Denver | Phoenix | Los Angeles | Chicago | New York |
|---|---|---|---|---|
| Winter (January 15, 2027) | 12:00 p.m. | 11:00 a.m. | 1:00 p.m. | 2:00 p.m. |
| Summer (July 15, 2027) | 11:00 a.m. | 11:00 a.m. | 1:00 p.m. | 2:00 p.m. |
Which states are in the Mountain Time Zone?
The Mountain zone lies between the Central–Mountain line (49 CFR 71.7) and the Mountain–Pacific line (49 CFR 71.9), as 49 CFR 71.8 defines it. All of Colorado, Utah, Wyoming, Montana, New Mexico and Arizona are in it. So is southern Idaho: the line follows the Salmon River, and Idaho south of it, including Boise, is on Mountain Time. Most of Malheur County in Oregon and West Wendover in Nevada are too. In the east, the western edges of North Dakota, South Dakota, Nebraska and Kansas, and El Paso and Hudspeth counties in Texas, are on Mountain Time.
Mountain Time, hour by hour (winter)
| Mountain Time | Pacific Time | Central Time | Eastern Time | UTC |
|---|---|---|---|---|
| 12:00 a.m. | 11:00 p.m. (−1 day) | 1:00 a.m. | 2:00 a.m. | 7:00 a.m. |
| 1:00 a.m. | 12:00 a.m. | 2:00 a.m. | 3:00 a.m. | 8:00 a.m. |
| 2:00 a.m. | 1:00 a.m. | 3:00 a.m. | 4:00 a.m. | 9:00 a.m. |
| 3:00 a.m. | 2:00 a.m. | 4:00 a.m. | 5:00 a.m. | 10:00 a.m. |
| 4:00 a.m. | 3:00 a.m. | 5:00 a.m. | 6:00 a.m. | 11:00 a.m. |
| 5:00 a.m. | 4:00 a.m. | 6:00 a.m. | 7:00 a.m. | 12:00 p.m. |
| 6:00 a.m. | 5:00 a.m. | 7:00 a.m. | 8:00 a.m. | 1:00 p.m. |
| 7:00 a.m. | 6:00 a.m. | 8:00 a.m. | 9:00 a.m. | 2:00 p.m. |
| 8:00 a.m. | 7:00 a.m. | 9:00 a.m. | 10:00 a.m. | 3:00 p.m. |
| 9:00 a.m. | 8:00 a.m. | 10:00 a.m. | 11:00 a.m. | 4:00 p.m. |
| 10:00 a.m. | 9:00 a.m. | 11:00 a.m. | 12:00 p.m. | 5:00 p.m. |
| 11:00 a.m. | 10:00 a.m. | 12:00 p.m. | 1:00 p.m. | 6:00 p.m. |
| 12:00 p.m. | 11:00 a.m. | 1:00 p.m. | 2:00 p.m. | 7:00 p.m. |
| 1:00 p.m. | 12:00 p.m. | 2:00 p.m. | 3:00 p.m. | 8:00 p.m. |
| 2:00 p.m. | 1:00 p.m. | 3:00 p.m. | 4:00 p.m. | 9:00 p.m. |
| 3:00 p.m. | 2:00 p.m. | 4:00 p.m. | 5:00 p.m. | 10:00 p.m. |
| 4:00 p.m. | 3:00 p.m. | 5:00 p.m. | 6:00 p.m. | 11:00 p.m. |
| 5:00 p.m. | 4:00 p.m. | 6:00 p.m. | 7:00 p.m. | 12:00 a.m. (+1 day) |
| 6:00 p.m. | 5:00 p.m. | 7:00 p.m. | 8:00 p.m. | 1:00 a.m. (+1 day) |
| 7:00 p.m. | 6:00 p.m. | 8:00 p.m. | 9:00 p.m. | 2:00 a.m. (+1 day) |
| 8:00 p.m. | 7:00 p.m. | 9:00 p.m. | 10:00 p.m. | 3:00 a.m. (+1 day) |
| 9:00 p.m. | 8:00 p.m. | 10:00 p.m. | 11:00 p.m. | 4:00 a.m. (+1 day) |
| 10:00 p.m. | 9:00 p.m. | 11:00 p.m. | 12:00 a.m. (+1 day) | 5:00 a.m. (+1 day) |
| 11:00 p.m. | 10:00 p.m. | 12:00 a.m. (+1 day) | 1:00 a.m. (+1 day) | 6:00 a.m. (+1 day) |
Standard time, for example January 15, 2027. Arizona matches the Denver column in winter and the Los Angeles column in summer.
Shift handovers across the Mountain zone
A company with sites in Denver and Phoenix works one hour apart from March to November and on the same clock in winter. Put the zone on every shared rota, and check the first week after each change. A 12-hour night shift in Denver lasts 13 hours on November 1, 2026 and 11 hours on March 14, 2027; in Phoenix it is always 12. The night shift clock change calculator counts the hours, and the shift calendar lays out your whole year.
More guides
Figures are worked out from each cycle; rules checked against official sources on . How we calculate
Questions
Is Colorado currently MST or MDT?
MDT until 2 a.m. on Sunday, November 1, 2026, then MST until Sunday, March 14, 2027.
Is Mountain Time the same as California?
No. Mountain Time is one hour ahead of California (Pacific Time) all year. Arizona is the exception: in summer it shows the same time as California.
Is AZ the same as MST right now?
Yes. Arizona uses Mountain Standard Time all year and does not observe daylight saving time (A.R.S. 1-242).
Is Mountain Time 2 hours behind EST?
Yes, Denver is 2 hours behind New York all year. Arizona is 2 hours behind in winter and 3 hours behind in summer.
Which states are in the Mountain Time Zone?
Colorado, Utah, Wyoming, Montana, New Mexico and Arizona, plus southern Idaho and parts of Oregon, Nevada, North Dakota, South Dakota, Nebraska, Kansas and Texas (49 CFR 71.7–71.9).