AT – Atlantic Time
The term Atlantic Time (AT) is often used to denote the local time in areas observing either Atlantic Daylight Time (ADT) or Atlantic Standard Time (AST).
Atlantic Standard Time is 4 hours behind Coordinated Universal Time (UTC).
Atlantic Daylight Time is 3 hours behind UTC.
In locations observing Daylight Saving Time (DST) during part of the year, Atlantic Time is not static but switches between ADT and AST.
Where and when is Atlantic Time observed?
North America
Canadian provinces using AST in the winter and ADT in the summer
- Most of Labrador (mainland part of the province of Newfoundland and Labrador)
- New Brunswick
- Nova Scotia
- Prince Edward Island
Areas of Greenland using AST in the winter and ADT in the summer
- Thule area
Atlantic
AST all year round
Some locations, such as the ones below don't switch and are in AST all year long.
North America
Canadian provinces using AST all year
- Quebec - East of 63 West only.
Caribbean
Caribbean countries/territories using AST all year
- Anguilla
- Antigua and Barbuda
- Aruba
- Barbados
- British Virgin Islands
- Caribbean Netherlands
- Curaçao
- Dominica
- Dominican Republic
- Grenada
- Guadeloupe
- Martinique
- Montserrat
- Puerto Rico
- Saint Barthélemy
- Saint Kitts and Nevis
- Saint Lucia
- Saint Martin (FR)
- Saint Vincent and Grenadines
- Sint Maarten (NL)
- Trinidad and Tobago
- Turks and Caicos Islands
- US Virgin Islands
- ADT will be observed in Halifax, Hamilton until Nov 6, 2016 at 2:00 AM
- UTC Offset: UTC -3
- 1 hour ahead of Washington DC
Find current time and time zone by city
Example cities
Canada – Halifax
Bermuda – Hamilton
Related time zones
AST – Atlantic Standard Time
ADT – Atlantic Daylight Time
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