Why Arizona Doesn't Observe DST

2026-02-05 · 8 min read

Most of Arizona has not observed daylight saving time since 1968. The main exception is the Navajo Nation, which does observe DST.

Why Arizona Opted Out

Arizona’s extreme summer heat makes later sunsets less attractive. An extra hour of evening daylight can increase cooling demand, so policymakers viewed DST as an energy cost rather than a benefit.

Navajo Nation and the “Timezone Donut”

The Navajo Nation spans Arizona, New Mexico, and Utah, so it follows DST to keep one consistent clock across reservation territory. The Hopi Reservation, surrounded by Navajo land in Arizona, does not observe DST, creating the well-known timezone-donut routing quirk.

Other U.S. Areas Without DST

• Hawaii
• Puerto Rico
• Guam
• U.S. Virgin Islands
• American Samoa

Permanent DST Debate

The Sunshine Protection Act passed the U.S. Senate unanimously in March 2022 but did not receive a House vote, so federal law remains unchanged.

Check time in Phoenix and the U.S. DST guide.