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DateAlmanac

What is AST in UTC?

Coordinated Universal Time is 4 hours ahead

Atlantic Time is on UTC−4:00 and Coordinated Universal Time is on UTC+0:00 right now. The gap changes during the year — see below.

Convert a time

UTC — Coordinated Universal Time

8:00 am

UTC, Sat

Time in Halifax
4:28:49 AM
Time in the prime meridian
8:28:49 AM
Difference
+4 h
Next clock change
March 14, 2027

When the difference changes

Atlantic Time and Coordinated Universal Time do not change their clocks on the same dates, so the gap between them is not the same all year. Most converters show only today’s figure. These are the periods ahead:

  1. Now – March 14, 2027Coordinated Universal Time is 4 hours ahead
  2. March 14, 2027 – November 7, 2027Coordinated Universal Time is 3 hours ahead
  3. November 7, 2027 – onwardsCoordinated Universal Time is 4 hours ahead

Periods shorter than a day are not listed. Each zone changes at its own local time, so on a date when both move there are a few hours when the gap is briefly something else.

Daylight saving

Atlantic Time

Sunday, March 14, 2027

Clocks go forward one hour — 2:00 am becomes 3:00 am local time, and the zone is on ADT after that.

Coordinated Universal Time

No clock changes

Coordinated Universal Time stays on UTC all year, so its offset from UTC never moves.

AST to UTC conversion table

Every hour of Saturday, November 7, 2026, converted from Atlantic Time to Coordinated Universal Time. 4 of the 24 hours fall on a different calendar day in the prime meridian, which is marked.

12:00 am AST
4:00 am UTC
1:00 am AST
5:00 am UTC
2:00 am AST
6:00 am UTC
3:00 am AST
7:00 am UTC
4:00 am AST
8:00 am UTC
5:00 am AST
9:00 am UTC
6:00 am AST
10:00 am UTC
7:00 am AST
11:00 am UTC
8:00 am AST
12:00 pm UTC
9:00 am AST
1:00 pm UTC
10:00 am AST
2:00 pm UTC
11:00 am AST
3:00 pm UTC
12:00 pm AST
4:00 pm UTC
1:00 pm AST
5:00 pm UTC
2:00 pm AST
6:00 pm UTC
3:00 pm AST
7:00 pm UTC
4:00 pm AST
8:00 pm UTC
5:00 pm AST
9:00 pm UTC
6:00 pm AST
10:00 pm UTC
7:00 pm AST
11:00 pm UTC
8:00 pm AST
12:00 am UTC+1 day
9:00 pm AST
1:00 am UTC+1 day
10:00 pm AST
2:00 am UTC+1 day
11:00 pm AST
3:00 am UTC+1 day

Scheduling between the two

Working hours overlap from 9:00 am to 2:00 pm AST, which is 1:00 pm to 6:00 pm UTC. Anything inside that window falls in the normal working day at both ends.

A note on AST: it can also mean Arabia Standard Time (UTC+3). This page means Atlantic Time.

Atlantic Time (AST) is used in Nova Scotia, New Brunswick and Puerto Rico

Coordinated Universal Time (UTC) is used in aviation, computing, and science worldwide. UTC never changes for daylight saving.

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