Idaho local data guide

Daylight Saving Time Observance in the United States

No, not all parts of the United States observe daylight saving time (DST). While the majority of the country, including Idaho, follows the biannual practice of shifting clocks forward in the spring and back in the autumn under the Uniform Time Act of 1966, select states and U.S. territories have opted out of the practice, remaining on standard time year-round.

Updated with grounded research as of 2026-10-16.

The short answer

No, daylight saving time is not observed uniformly across the United States. While most states—including all of Idaho—adhere to the biannual clock change, certain states and territories maintain standard time throughout the year. It is important for residents and those planning relocations to recognize that federal law currently dictates these timekeeping standards, limiting the ability of individual states to make permanent changes without congressional intervention.

Key facts

States Opting Out of DST
Hawaii and Arizona (with the exception of the Navajo Nation) do not observe daylight saving time.
Idaho's Status
As of October 16, 2026, the entire state of Idaho observes daylight saving time in accordance with federal law.
Territories Opting Out
American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the U.S. Virgin Islands do not observe DST.

Understanding Idaho's Timekeeping

Idaho adheres to the federal standard established by the Uniform Time Act of 1966. Residents across the state, whether in the Mountain Time Zone or the Pacific Time Zone (which covers the Idaho Panhandle), participate in the biannual shift: moving clocks forward one hour in the spring and back one hour in the autumn.

  • Spring: Clocks move forward, resulting in one hour less of sleep but an extra hour of daylight in the evening.
  • Autumn: Clocks move back, providing one extra hour of sleep and earlier sunsets.

The Federal Constraint on State Legislation

While 19 states have passed legislation or resolutions expressing an intent to move to permanent daylight saving time, these measures are currently largely symbolic or unenforceable as written. The Uniform Time Act allows states to exempt themselves from DST—choosing to stay on standard time year-round—but it does not grant them the authority to observe daylight saving time permanently without approval from the U.S. Congress.

  • States can opt out of DST and remain on Standard Time.
  • States cannot implement permanent DST without federal legislative action.

Tribal Nations and Unique Exceptions

Geography and local governance can occasionally override state-wide trends. For example, while the state of Arizona does not observe daylight saving time, the Navajo Nation—which spans parts of Arizona, New Mexico, and Utah—chooses to observe DST. This is a critical factor for individuals relocating to or planning travel within the American Southwest.

  • The Navajo Nation observes DST to maintain consistency with its land holdings in neighboring states.
  • Travelers crossing from Arizona into the Navajo Nation may experience time differences.

Common questions

Does Idaho plan to switch to permanent daylight saving time?

As of October 2026, while there is ongoing national debate, Idaho remains on the standard biannual rotation. Any change to 'permanent' daylight saving time would require specific authorization from the U.S. Congress, which has not yet been granted for any state.

Why does the Navajo Nation observe DST while Arizona does not?

The Navajo Nation opted to observe daylight saving time to ensure that the time is uniform across its territory, which extends into Utah and New Mexico—both of which observe daylight saving time.

Related Idaho questions

  • What is the status of the Sunshine Protection Act?
  • How do I determine if a region I am moving to observes daylight saving time?
  • Can a state choose to be on permanent standard time instead of daylight saving time?

Sources and verification