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Atlantic Time (AST / ADT)

Atlantic Time is UTC−4 in winter (Atlantic Standard Time) and UTC−3 in summer (Atlantic Daylight Time).

Right now on Atlantic Time
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AST / ADT · UTC−4 in winter, UTC−3 in summer

Key facts

Full nameAtlantic Time
CodeAST / ADT
UTC offsetUTC−4 in winter, UTC−3 in summer
Daylight savingYes

AST in winter, ADT in summer.

When the clocks change

Clocks go forward one hour at 2 AM on the second Sunday in March and back one hour at 2 AM on the first Sunday in November.

DateChangeNew offset
Mar 14, 2027Clocks go forward 1 hourUTC−3
Nov 7, 2027Clocks go back 1 hourUTC−4

Where it's used

Time in HalifaxTime in MonctonTime in FrederictonTime in Charlottetown

One step west and east

Earlier · to the westManitoba Time–EST · UTC−5 all yearManitoba Time is 1 hour behind Atlantic Time in winter and 2 hours behind in summer.Earlier · to the westEastern Time–EST / EDT · UTC−5 / UTC−4Eastern Time is 1 hour behind Atlantic Time all year.Later · to the eastNewfoundland Time–NST / NDT · UTC−3:30 / UTC−2:30Newfoundland Time is 30 minutes ahead of Atlantic Time all year.

Questions

What is Atlantic Time?

Atlantic Time is UTC−4 in winter (Atlantic Standard Time) and UTC−3 in summer (Atlantic Daylight Time).

What is the Atlantic Time code?

AST in winter, ADT in summer.

Does Atlantic Time change for daylight saving time?

Yes. Clocks go forward one hour at 2 AM on the second Sunday in March and back one hour at 2 AM on the first Sunday in November. The next changes are Mar 14, 2027 and Nov 7, 2027.

What is the difference between Atlantic Time and Manitoba Time?

Manitoba Time is 1 hour behind Atlantic Time in winter and 2 hours behind in summer.

What is the difference between Atlantic Time and Eastern Time?

Eastern Time is 1 hour behind Atlantic Time all year.

What is the difference between Atlantic Time and Newfoundland Time?

Newfoundland Time is 30 minutes ahead of Atlantic Time all year.