About Atlantic Time
Atlantic Time is used in the Canadian Maritime provinces (Nova Scotia, New Brunswick and Prince Edward Island) and Bermuda. Puerto Rico and much of the Caribbean use Atlantic Standard Time all year without daylight saving.
Daylight saving time
Atlantic Time switches between Atlantic Standard Time (AST, UTC−4) and Atlantic Daylight Time (ADT, UTC−3).
- Sunday, March 8, 2026: clocks go forward from 2:00 AM to 3:00 AM (ADT begins)
- Sunday, November 1, 2026: clocks go back from 2:00 AM to 1:00 AM (AST begins)
- Sunday, March 14, 2027: clocks go forward from 2:00 AM to 3:00 AM (ADT begins)
- Sunday, November 7, 2027: clocks go back from 2:00 AM to 1:00 AM (AST begins)
Cities on this clock
AT vs. other time zones
| Time zone | Now | vs. AST | Converter |
|---|---|---|---|
| Eastern Time EST/EDT | — | — | |
| Central Time CST/CDT | — | — | |
| Mountain Time MST/MDT | — | — | |
| Pacific Time PST/PDT | — | — | |
| Alaska Time AKST/AKDT | — | — | |
| Hawaii Time HST | — | — | |
| Greenwich Mean Time GMT | — | — | |
| Coordinated Universal Time UTC | — | — | |
| Central European Time CET/CEST | — | — | |
| Eastern European Time EET/EEST | — | — | |
| India Standard Time IST | — | — | |
| Japan Standard Time JST | — | — | |
| Australian Eastern Time AEST/AEDT | — | — | |
| Singapore Time SGT | — | — | |
| Philippine Time PHT | — | — | |
| Moscow Time MSK | — | — | |
| Gulf Standard Time GST | — | — |
Times update live. Plan a meeting across time zones.
Questions
What is the difference between AST and ADT?
AST (Atlantic Standard Time) is the winter time, UTC−4. ADT (Atlantic Daylight Time) is the daylight saving time used in summer, UTC−3. People often say AST all year, but strictly ADT applies while daylight saving is in effect.
When does Atlantic Time change in 2026?
In 2026, clocks on Atlantic Time go forward on Sunday, March 8, 2026 and back on Sunday, November 1, 2026.
Where is Atlantic Time used?
Atlantic Time is used in the Canadian Maritime provinces (Nova Scotia, New Brunswick and Prince Edward Island) and Bermuda. Puerto Rico and much of the Caribbean use Atlantic Standard Time all year without daylight saving.
What is AST in UTC?
AST is UTC−4 and ADT is UTC−3.