Arizona Time Zone Map

Arizona is on Mountain Standard Time, UTC-7, all year. Phoenix, Tucson, Flagstaff, Scottsdale, Mesa and every other Arizona city keep the same clock in January and July. The time zone database shows that Phoenix did follow daylight time in 1967, the first summer of the federal Uniform Time Act, and that the state dropped it again in 1968 when the legislature used the exemption the Act allows.

The reason usually given is heat. An extra hour of daylight in the evening does not help in a state where afternoons pass 110°F (43°C), because it pushes the hottest part of the day later, when people are out. Hawaii also skips daylight time, so Arizona and Hawaii are the only two states that never change their clocks.

The Navajo Nation, whose land covers northeast Arizona and parts of Utah and New Mexico, observes daylight time so that the whole Nation runs on one clock. In summer a Navajo Nation community such as Window Rock or Kayenta is on UTC-6, one hour ahead of Flagstaff, which is not far away. In winter both are on UTC-7.

The Hopi Reservation sits inside Navajo land and follows the rest of Arizona, so it stays on UTC-7 all year. A drive through the area in summer can therefore cross from Arizona time to Navajo time and back again, and the clocks agree again every winter.

A call fixed at 10:00 AM Phoenix time is 10:00 AM in Los Angeles in summer and 9:00 AM in winter, and it is 12:00 PM in New York in winter and 1:00 PM in summer. The Arizona side never moves, so a recurring invite stored in Phoenix time shifts for everyone else in March and November, and one stored in another city's time shifts for Arizona.

Give the city and the zone in the invite. The UTC to MST converter shows Arizona's fixed offset against UTC for every hour, and the 2026 daylight saving page lists the dates on which everyone else moves.