Atlantic Time (AT) or the Atlantic Time Zone. This can add a bit of confusion as the term Atlantic Time does not differentiate between standard time and Daylight Saving Time, so Atlantic Time switches between AST and ADT in areas that use DST during part of the year.

Most North American time zones have generic terms, including Pacific Time (PT), Mountain Time (MT), Central Time (CT), and Eastern Time (ET).

Converting Atlantic Standard Time to Other US Time Zones

• Atlantic Standard Time (AST) is 1 hour ahead of Eastern Standard Time (EST).
  To convert AST to EST, you have to subtract one hour.
• Atlantic Standard Time (AST) is 2 hours ahead of Central Standard Time (CST).
  To convert AST to CST, you have to subtract two hours.
• Atlantic Standard Time (AST) is 3 hours ahead of Mountain Standard Time (MST).
  To convert AST to MST, you have to subtract three hours.
• Atlantic Standard Time (AST) is 4 hours ahead of Pacific Standard Time (PST).
  To convert AST to PST, you have to subtract four hours.

Time Zone Converter: UTC to AST

Where and When is AST Observed?

North America

Atlantic

Caribbean

Other Time Zones in UTC -4

Some time zones exist that have the same offset as AST, but can be found under a different name:

• AMT – Amazon Time
• BOT – Bolivia Time
• CDT – Cuba Daylight Time
• CIDST – Cayman Islands Daylight Saving Time
• CLT – Chile Standard Time
• EDT – Eastern Daylight Time
• FKT – Falkland Island Time
• GYT – Guyana Time
• Q – Quebec Time Zone
• VET – Venezuelan Standard Time