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
Hawaii-Aleutian Standard and Daylight Time
Hawaii Time observes standard time at ten hours behind UTC (UTC-10), based on the mean solar time of the 150th meridian west of Greenwich.
The zone's full name, Hawaii-Aleutian Time, combines the two places where it's observed: Hawaii itself, and the part of Alaska's Aleutian Islands west of 169°30′ W longitude. The Aleutian portion observes daylight saving time, shifting to Hawaii-Aleutian Daylight Time (HADT, UTC-9) — but Hawaii keeps Hawaii-Aleutian Standard Time (HAST) year-round, never shifting at all.
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.
