US Time Zone Map: Every Time Zone in America Explained
The contiguous US has four time zones, and if you include Alaska and Hawaii, that makes six. If you really want to get technical and include US territories like Guam and Puerto Rico, you are looking at nine. But let us stick to the six you will actually deal with.
The Four Contiguous Time Zones
| Time Zone | UTC Offset (Standard) | UTC Offset (DST) | Major Cities |
|---|---|---|---|
| Eastern (ET) | UTC-5 | UTC-4 | New York, Washington DC, Miami, Atlanta |
| Central (CT) | UTC-6 | UTC-5 | Chicago, Dallas, Houston, Minneapolis |
| Mountain (MT) | UTC-7 | UTC-6 | Denver, Phoenix, Salt Lake City, Albuquerque |
| Pacific (PT) | UTC-8 | UTC-7 | Los Angeles, Seattle, San Francisco, Las Vegas |
Then There Is Alaska and Hawaii
- Alaska Time (AKST): UTC-9 standard, UTC-8 during DST. Anchorage, Fairbanks, Juneau.
- Hawaii-Aleutian Time (HST): UTC-10, no DST. Honolulu stays put year-round.
The Arizona Exception
Arizona does not observe daylight saving time. This means for half the year, Phoenix is on the same time as Los Angeles (Pacific Daylight Time), and for the other half it is on the same time as Denver (Mountain Standard Time).
Why? Arizona's reasoning is hot-weather logic: when it is 110 F in the summer, the last thing people want is an extra hour of evening heat. By staying on Mountain Standard Time year-round, the sun sets earlier and morning temperatures are more bearable for outdoor activity.
The Navajo Nation within Arizona does observe DST though, which creates the surreal situation of driving from a DST-observing area into a non-DST area and back again. Within a single reservation surrounded by Arizona, you change time zones six times a year.
How This Messes Up Scheduling
Three common mistakes:
- The sports broadcast problem: A game at 8 PM Eastern is 5 PM Pacific -- but during DST transitions (March and November), the offset might be 3 or 4 hours instead of the usual 3. Someone will arrive an hour early.
- The Arizona-in-summer problem: From March to November, Phoenix = Los Angeles time, not Denver time. Lots of people get this wrong.
- The Indiana problem: Indiana used to have insane time zone fragmentation -- some counties on Eastern, some on Central, some observing DST, some not. Most counties switched to DST in 2006, but some northwest and southwest counties still stay on Eastern year-round and just do not spring forward.