GUIDES · TIME ZONES
Arizona time zone: why most of Arizona skips daylight saving
Quick answer
Arizona uses Mountain Standard Time (MST, UTC−7) all year and doesn’t change its clocks. In winter, Phoenix has the same time as Denver; in summer, when the rest of the Mountain zone moves to UTC−6, Phoenix has the same time as Los Angeles. The exception is the Navajo Nation in the northeast, which does use daylight saving time.
Arizona compared with other US cities
Because Arizona stays put while most of the US changes its clocks, the difference between Arizona and the rest of the country changes twice a year.
| Compared with | Winter (November–March) | Summer (March–November) |
|---|---|---|
| Los Angeles | Phoenix is 1 hour ahead | Same time |
| Denver | Same time | Phoenix is 1 hour behind |
| Chicago | Phoenix is 1 hour behind | Phoenix is 2 hours behind |
| New York | Phoenix is 2 hours behind | Phoenix is 3 hours behind |
The rest of the US changes its clocks on the second Sunday in March and the first Sunday in November. Arizona’s clocks don’t move on either date.
Why Arizona doesn’t change its clocks
Arizona tried daylight saving time in 1967, the first year the federal Uniform Time Act applied, and repealed it by state law in 1968. The usual explanation is the climate: in a desert summer, an extra hour of evening sun means more heat and more air conditioning, not more pleasant evenings. Hawaii is the only other US state that stays on standard time all year.
What it means for meetings
If you have a regular call with someone in Arizona, it moves twice a year for everyone except them. A 9 AM call set in Phoenix is 11 AM in New York in winter and noon in summer. Put the Arizona time in the invite, or use a calendar app that understands time zones; don’t write “MT” or “Mountain Time”, which is ambiguous in summer.
On phones and computers, the Arizona time zone is called America/Phoenix. The Navajo Nation uses America/Denver.
Common questions
Does Arizona change its clocks?
No. Most of Arizona stays on Mountain Standard Time (UTC−7) all year. The Navajo Nation in the northeast is the exception: it moves its clocks forward in March and back in November like the rest of the US.
Is Arizona on Pacific time in the summer?
Not officially. Arizona stays on Mountain Standard Time, but in summer that’s the same clock time as Pacific Daylight Time, so Phoenix and Los Angeles show the same time from March to November.
What time zone is Phoenix in?
Phoenix is on Mountain Standard Time (MST, UTC−7) all year, with no daylight saving time. On computers and phones the zone is called America/Phoenix.
Check Arizona time
Compare Phoenix with your own cities in the time converter, which applies each place’s rules for the date you pick.