Hawaii Time
Hawaii-Aleutian Standard Time - HAST (UTC-10)
Hawaii-Aleutian Daylight Time - HADT (UTC-9)
Honolulu
Alaska Time
Alaska Standard Time - AKST (UTC-9)
Alaska Daylight Time - AKDT (UTC-8)
Anchorage
Pacific Time
Pacific Standard Time - PST (UTC-8)
Pacific Daylight Time - PDT (UTC-7)
Vancouver
Las Vegas
Los Angeles
Mountain Time
Mountain Standard Time - MST (UTC-7)
Mountain Daylight Time - MDT (UTC-6)
Edmonton
Denver
Phoenix
Central Time
Central Standard Time - CST (UTC-6)
Central Daylight Time - CDT (UTC-5)
Winnipeg
Chicago
Eastern Time
Eastern Standard Time - EST (UTC-5)
Eastern Daylight Time - EDT (UTC-4)
Toronto
New York
Atlantic Time
Atlantic Standard Time - AST (UTC-4)
Atlantic Daylight Time - ADT (UTC-3)
Halifax
Newfoundland Time
Newfoundland Standard Time - NST (UTC-3:30)
Newfoundland Daylight Time - NDT (UTC-2:30)
St. John's
Alaska Standard and Daylight Time
Alaska observes standard time at nine hours behind UTC (UTC-9), shifting to eight hours behind (UTC-8) during daylight saving time — one hour behind Pacific Time. Standard time in the zone is based on the mean solar time of the 135th meridian west of Greenwich. In the United States, it's generally called Alaska Time, specifically Alaska Standard Time (AKST) during winter and Alaska Daylight Time (AKDT) during daylight saving time. Since 2007, the shift from AKST to AKDT takes place at 2:00 a.m. on the second Sunday of March, and the shift back to AKST takes place at 2:00 a.m. on the first Sunday of November.
Alaska Is Divided Into Two Time Zones
The western Aleutian Islands actually observe Hawaii-Aleutian Time, one hour behind the rest of the state. Alaska is the largest U.S. state by far — larger than all but 18 countries in the world, and about a fifth of the combined land area of the other 48 states. Its territory spans nearly as much longitude as the entire continental United States, so strictly by geography it would fall into four separate time zones; political considerations settled on two instead.
Daylight Saving Time in the USA and Canada
Daylight saving time begins at 2:00 a.m. on the second Sunday of March and ends at 2:00 a.m. on the first Sunday of November, in every USA and Canada time zone that observes it.
North America DST Change Dates
| Year | Begins | Ends |
|---|---|---|
| 2021 | Sunday, 14 March, 02:00 | Sunday, 7 November, 02:00 |
| 2022 | Sunday, 13 March, 02:00 | Sunday, 6 November, 02:00 |
| 2023 | Sunday, 12 March, 02:00 | Sunday, 5 November, 02:00 |
| 2024 | Sunday, 10 March, 02:00 | Sunday, 3 November, 02:00 |
| 2025 | Sunday, 9 March, 02:00 | Sunday, 2 November, 02:00 |
| 2026 | Sunday, 8 March, 02:00 | Sunday, 1 November, 02:00 |
| 2027 | Sunday, 14 March, 02:00 | Sunday, 7 November, 02:00 |
| 2028 | Sunday, 12 March, 02:00 | Sunday, 5 November, 02:00 |
| 2029 | Sunday, 11 March, 02:00 | Sunday, 4 November, 02:00 |
| 2030 | Sunday, 10 March, 02:00 | Sunday, 3 November, 02:00 |
| 2031 | Sunday, 9 March, 02:00 | Sunday, 2 November, 02:00 |
Daylight saving time begin and end dates in the USA and Canada.
North American Time Zones
The same eight time zones from the comparison above, organized by UTC offset instead of by name — useful for seeing which zones share a clock time once daylight saving time shifts them.
Time Zones by UTC Offset
| UTC Offset | Standard Time | Daylight Time |
|---|---|---|
| UTC-10 | Hawaii-Aleutian | — |
| UTC-9 | Alaska | Hawaii-Aleutian |
| UTC-8 | Pacific | Alaska |
| UTC-7 | Mountain | Pacific |
| UTC-6 | Central | Mountain |
| UTC-5 | Eastern | Central |
| UTC-4 | Atlantic | Eastern |
| UTC-3:30 | Newfoundland | — |
| UTC-3 | — | Atlantic |
| UTC-2:30 | — | Newfoundland |
Time zones in North America, by UTC offset.
GMT and UTC
Greenwich Mean Time (GMT) originally referred to mean solar time at the Royal Observatory in Greenwich, London. Coordinated Universal Time (UTC) is the modern, atomic-clock-based standard that has replaced it for precise timekeeping — but the two are close enough that they're used interchangeably in everyday contexts, including throughout this page.
