The United States spans six main time zones across its 50 states, plus additional time zones for its territories. It is one of the most time-zone-complex countries in the world — not just because of its geographic size, but because of the unusual exceptions: states that do not observe Daylight Saving Time, counties that use a different time zone from the rest of their state, and territories that operate on entirely separate schedules.

This guide covers every US state's time zone, explains the DST rules, and walks through the unusual cases that trip people up most often.

The Six Main US Time Zones

The contiguous 48 states use four time zones. Alaska and Hawaii each have their own. Here is the full picture:

State-by-State Time Zone Reference

Here is the time zone for every US state:

The Arizona Exception: No Daylight Saving Time

Arizona is the most well-known time zone exception in the US. The state observes Mountain Standard Time (UTC−7) year-round and does not participate in Daylight Saving Time. The official reason is that Arizona's hot desert climate means residents prefer cooler evenings, and shifting an hour of daylight to the evening in summer would make the already extreme heat even more uncomfortable.

The practical consequence is that Arizona's time relationship with neighbouring states changes twice a year. In winter, Arizona is on the same time as Utah, Colorado, and New Mexico (all Mountain Standard Time). In summer, when those states spring forward to Mountain Daylight Time (UTC−6), Arizona stays at UTC−7 — making it one hour behind its neighbours.

The exception to the exception: the Navajo Nation, which covers a large area of northeastern Arizona (as well as parts of Utah and New Mexico), does observe Daylight Saving Time. And within the Navajo Nation, the Hopi Reservation does not observe DST. This creates a situation where driving across northeastern Arizona can mean crossing in and out of DST multiple times.

Indiana's Complex History

Indiana has one of the most complicated time zone histories of any US state. For decades, different counties in Indiana observed different time zones and different DST rules, creating a patchwork that confused residents and businesses alike. Some counties were on Eastern Standard Time year-round. Others were on Central Standard Time year-round. Others observed DST and others did not.

In 2006, Indiana standardised: the entire state moved to Eastern Time with full DST observance, except for a small number of counties in the northwest (near Chicago) and southwest (near Evansville) that were granted permission to remain on Central Time. Today, Indiana is mostly Eastern Time, but those border counties remain on Central Time.

US Territories and Their Time Zones

Beyond the 50 states, the US has several territories with their own time zones:

When Do US Clocks Change?

The US observes Daylight Saving Time from the second Sunday in March to the first Sunday in November. On the spring change date, clocks spring forward one hour at 2:00 AM local time (becoming 3:00 AM). On the autumn change date, clocks fall back one hour at 2:00 AM local time (becoming 1:00 AM).

This is different from the European DST schedule, which changes on the last Sunday in March and the last Sunday in October. The mismatch between US and European DST dates means there are two periods each year — roughly two weeks in spring and two weeks in autumn — when the time difference between the US and Europe is one hour different from its normal value.

Key Takeaways

Need to check the current time in any US city? Use the UrbanGlobalTrends Time Zone Converter for instant, accurate results including DST.