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DateAlmanac

What is AEST in AST?

Atlantic Time is 13 hours behind

Australian Eastern Time is on UTC+10:00 and Atlantic Time is on UTC−3:00 right now. Atlantic Time is on daylight saving, so its clocks read ADT. The gap changes during the year — see below.

Time in Sydney
10:52:29 PM
Time in Halifax
9:52:29 AM
Difference
−13 h
Next clock change
October 4, 2026

Convert a time

ADT — Atlantic Time

9:00 am

ADT, Fri

When the difference changes

Australian Eastern Time and Atlantic 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 – October 4, 2026Atlantic Time is 13 hours behind
  2. October 4, 2026 – November 1, 2026Atlantic Time is 14 hours behind
  3. November 1, 2026 – March 14, 2027Atlantic Time is 15 hours behind
  4. March 14, 2027 – April 4, 2027Atlantic Time is 14 hours behind
  5. April 4, 2027 – October 3, 2027Atlantic Time is 13 hours behind
  6. October 3, 2027 – onwardsAtlantic Time is 14 hours behind

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

Australian Eastern Time

Sunday, October 4, 2026

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

Atlantic Time

Sunday, November 1, 2026

Clocks go back one hour — 2:00 am becomes 1:00 am local time, and the zone is on AST after that.

AEST to AST conversion table

Every hour of Friday, September 25, 2026, converted from Australian Eastern Time to Atlantic Time. 13 of the 24 hours fall on a different calendar day in Halifax, which is marked.

12:00 am AEST
11:00 am ADT−1 day
1:00 am AEST
12:00 pm ADT−1 day
2:00 am AEST
1:00 pm ADT−1 day
3:00 am AEST
2:00 pm ADT−1 day
4:00 am AEST
3:00 pm ADT−1 day
5:00 am AEST
4:00 pm ADT−1 day
6:00 am AEST
5:00 pm ADT−1 day
7:00 am AEST
6:00 pm ADT−1 day
8:00 am AEST
7:00 pm ADT−1 day
9:00 am AEST
8:00 pm ADT−1 day
10:00 am AEST
9:00 pm ADT−1 day
11:00 am AEST
10:00 pm ADT−1 day
12:00 pm AEST
11:00 pm ADT−1 day
1:00 pm AEST
12:00 am ADT
2:00 pm AEST
1:00 am ADT
3:00 pm AEST
2:00 am ADT
4:00 pm AEST
3:00 am ADT
5:00 pm AEST
4:00 am ADT
6:00 pm AEST
5:00 am ADT
7:00 pm AEST
6:00 am ADT
8:00 pm AEST
7:00 am ADT
9:00 pm AEST
8:00 am ADT
10:00 pm AEST
9:00 am ADT
11:00 pm AEST
10:00 am ADT

Scheduling between the two

There is no overlap between a nine-to-six working day in Sydney and one in Halifax — the gap is too wide. A call has to sit early or late for one side. Early morning in Sydney is the usual compromise, since that is late afternoon or evening in Halifax.

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

Australian Eastern Time (AEST) is used in Melbourne, Canberra and Brisbane. Queensland stays on AEST all year while the southern states move to AEDT.

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

Other conversions