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DateAlmanac

What is ACST in MST?

Mountain Time is 17 hours 30 minutes behind

Australian Central Time is on UTC+10:30 and Mountain Time is on UTC−7:00 right now. Australian Central Time is on daylight saving, so its clocks read ACDT. The gap changes during the year — see below.

Convert a time

MST — Mountain Time

12:30 am

MST, Sat

Time in Adelaide
6:59:17 PM
Time in Denver
1:29:17 AM
Difference
−17:30 h
Next clock change
March 14, 2027

When the difference changes

Australian Central Time and Mountain 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, 2027Mountain Time is 17 hours 30 minutes behind
  2. March 14, 2027 – April 4, 2027Mountain Time is 16 hours 30 minutes behind
  3. April 4, 2027 – October 3, 2027Mountain Time is 15 hours 30 minutes behind
  4. October 3, 2027 – November 7, 2027Mountain Time is 16 hours 30 minutes behind
  5. November 7, 2027 – onwardsMountain Time is 17 hours 30 minutes 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 Central Time

Sunday, April 4, 2027

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

Mountain Time

Sunday, March 14, 2027

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

ACST to MST conversion table

Every hour of Saturday, November 7, 2026, converted from Australian Central Time to Mountain Time. 18 of the 24 hours fall on a different calendar day in Denver, which is marked.

12:00 am ACDT
6:30 am MST−1 day
1:00 am ACDT
7:30 am MST−1 day
2:00 am ACDT
8:30 am MST−1 day
3:00 am ACDT
9:30 am MST−1 day
4:00 am ACDT
10:30 am MST−1 day
5:00 am ACDT
11:30 am MST−1 day
6:00 am ACDT
12:30 pm MST−1 day
7:00 am ACDT
1:30 pm MST−1 day
8:00 am ACDT
2:30 pm MST−1 day
9:00 am ACDT
3:30 pm MST−1 day
10:00 am ACDT
4:30 pm MST−1 day
11:00 am ACDT
5:30 pm MST−1 day
12:00 pm ACDT
6:30 pm MST−1 day
1:00 pm ACDT
7:30 pm MST−1 day
2:00 pm ACDT
8:30 pm MST−1 day
3:00 pm ACDT
9:30 pm MST−1 day
4:00 pm ACDT
10:30 pm MST−1 day
5:00 pm ACDT
11:30 pm MST−1 day
6:00 pm ACDT
12:30 am MST
7:00 pm ACDT
1:30 am MST
8:00 pm ACDT
2:30 am MST
9:00 pm ACDT
3:30 am MST
10:00 pm ACDT
4:30 am MST
11:00 pm ACDT
5:30 am MST

Scheduling between the two

Working hours overlap from 9:00 am to 12:00 pm ACDT, which is 3:30 pm to 6:30 pm MST. Anything inside that window falls in the normal working day at both ends.

Australian Central Time (ACDT) is used in South Australia and the Northern Territory, on a half-hour offset from the east coast

Mountain Time (MST) is used in Salt Lake City, Albuquerque and Calgary. Arizona keeps MST all year and does not follow MDT.

Other conversions