What is MST in ART?
Argentina Time is 3 hours ahead
Mountain Time is on UTC−6:00 and Argentina Time is on UTC−3:00 right now. Mountain Time is on daylight saving, so its clocks read MDT. The gap changes during the year — see below.
- Time in Denver
- 8:56 pm
- Time in Buenos Aires
- 11:56 pm
- Difference
- +3 h
- Next clock change
- November 1, 2026
Convert a time
ART — Argentina Time
11:00 pm
Tue
When the difference changes
Mountain Time and Argentina 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:
- Now – November 1, 2026Argentina Time is 3 hours ahead
- November 1, 2026 – March 14, 2027Argentina Time is 4 hours ahead
- March 14, 2027 – onwardsArgentina Time is 3 hours ahead
Periods shorter than a day are not listed: both zones change at 2am in their own local time, so there are a few hours on each transition date when the gap is briefly something else.
Daylight saving
Mountain Time
Clocks go back one hour at 2am local time, becoming MST.
Argentina Time
Argentina Time stays on ART all year, so its offset from UTC never moves.
MST to ART conversion table
Every hour of Tuesday, September 22, 2026, converted from Mountain Time to Argentina Time. 3 of the 24 hours fall on a different calendar day in Buenos Aires, which is marked.
- 12:00 am MDT
- 3:00 am ART
- 1:00 am MDT
- 4:00 am ART
- 2:00 am MDT
- 5:00 am ART
- 3:00 am MDT
- 6:00 am ART
- 4:00 am MDT
- 7:00 am ART
- 5:00 am MDT
- 8:00 am ART
- 6:00 am MDT
- 9:00 am ART
- 7:00 am MDT
- 10:00 am ART
- 8:00 am MDT
- 11:00 am ART
- 9:00 am MDT
- 12:00 pm ART
- 10:00 am MDT
- 1:00 pm ART
- 11:00 am MDT
- 2:00 pm ART
- 12:00 pm MDT
- 3:00 pm ART
- 1:00 pm MDT
- 4:00 pm ART
- 2:00 pm MDT
- 5:00 pm ART
- 3:00 pm MDT
- 6:00 pm ART
- 4:00 pm MDT
- 7:00 pm ART
- 5:00 pm MDT
- 8:00 pm ART
- 6:00 pm MDT
- 9:00 pm ART
- 7:00 pm MDT
- 10:00 pm ART
- 8:00 pm MDT
- 11:00 pm ART
- 9:00 pm MDT
- 12:00 am ART+1 day
- 10:00 pm MDT
- 1:00 am ART+1 day
- 11:00 pm MDT
- 2:00 am ART+1 day
Scheduling between the two
Working hours overlap from 9:00 am to 3:00 pm MDT, which is 12:00 pm to 6:00 pm ART. Anything inside that window falls in the normal working day at both ends.
Mountain Time (MDT) is used in Salt Lake City, Albuquerque and Calgary. Arizona keeps MST all year and does not follow MDT.