In the United StatesWhile most states change their clocks twice a year to better align with daylight hours, a few states and territories have chosen not to follow this practice. These exceptions remain Standard time all year round, thus avoiding the biannual time changes that occur in most parts of the country.

Although Daylight Saving Time (DST) Although Daylight Saving Time is widely used, some states and territories choose not to use it for practical and geographic reasons. Whether due to minimal differences in daylight hours or special climatic conditions, these areas have received little or no benefit from the change to Daylight Saving Time.

States where daylight saving time does not apply

Hawaii
Hawaii, known for its tropical climate and geographic isolation, does not observe daylight saving time. Due to its proximity to the equator, the variation in daylight hours throughout the year is minimal, so no time changes are necessary.

Arizona (except the Navajo Nation)
Arizona has chosen not to observe daylight saving time primarily because of its extremely hot climate. By not setting the clocks forward or back, Arizona’s hottest part of the day is less stressed, resulting in less energy being used for air conditioning. However, the Navajo Nation, which spans parts of Arizona, Utah, and New Mexico, observes daylight saving time, unlike the rest of the state.

US territories that do not change their clocks

Puerto Rico
Since Puerto Rico is a Caribbean territory, there are little variations in daylight hours throughout the year due to its proximity to the equator. For this reason, Puerto Rico does not observe daylight saving time.

Guam
This US territory in the Pacific also observes standard time year-round. As with other island territories, Guam has only minimal differences in the length of daylight, so no time changes are necessary.

American Samoa
American Samoa is located in the South Pacific and follows a similar pattern to Guam and Puerto Rico: it observes standard time all year round.

US Virgin Islands
The U.S. Virgin Islands, located in the Caribbean, also do not observe daylight saving time because the hours of daylight change only minimally throughout the year.

Reasons for not observing daylight saving time

The states and territories that do not observe daylight saving time often do so for geographic or practical reasons. In areas near the equator, such as Hawaii, Puerto Rico and Guam, there is little variation in daylight hours throughout the year, so the time change offers little benefit.

In Arizona, the main reason is the climate. Summer temperatures in this state can be extremely high. Following standard time helps minimize heat stress during peak hours, reduce the need for air conditioning, and reduce energy consumption.

Summary of states and territories that do not observe daylight saving time

The Navajo Nation: An exception in Arizona

Interestingly, there is no daylight saving time in most parts of Arizona, Navajo Nation does. This exception exists because the Navajo Nation extends across Arizona, Utah, and New Mexico, where daylight saving time is observed. The Navajo Nation has chosen to maintain uniformity throughout its territory, which includes areas outside of Arizona.

Future perspectives for summer time

Although some states and territories have opted against daylight saving time, the debate over its usefulness remains a national issue. In recent years, there have been growing efforts to make daylight saving time permanent in some states, although such changes require federal government approval.

The varying adoption of DST across the United States reflects the different needs and geographic conditions of each state and territory. As this discussion continues, we may see further exceptions or even a more comprehensive national change in timekeeping across the country.