Daylight Saving Time Isn't Observed in These U.S. States, Territories That Don't 'Fall Back'

What is Daylight Saving Time (DST)?

Daylight Saving Time (DST) is a practice of advancing clocks during summer months so that evening daylight lasts longer. The Uniform Time Act of 1966 establishes DST as a national observance starting on the first Sunday of April and ending on the first Sunday of November.

Which U.S. States Do Not Observe DST?

There are two U.S. states that do not observe Daylight Saving Time:

• Arizona
• Hawaii

Additionally, several U.S. territories do not observe DST:

• American Samoa
• Guam
• Northern Mariana Islands
• Puerto Rico
• U.S. Virgin Islands

Why Don't These States and Territories Observe DST?

The reasons for not observing DST vary among states and territories. In the case of Arizona, the state legislature voted in 1968 to eliminate DST due to concerns about increased energy consumption and the disruption of business and agricultural activities.

Hawaii, due to its proximity to the equator, experiences minimal seasonal variation in daylight hours, making DST less necessary.

U.S. territories like Guam and Puerto Rico are located in the tropics, where daylight hours remain relatively constant throughout the year, making DST unnecessary.

Conclusion

While most U.S. states and territories observe Daylight Saving Time, there are a few exceptions. The states of Arizona and Hawaii, as well as several U.S. territories, do not adjust their clocks for DST due to geographic, economic, and cultural factors.