What is MDT?
MDT stands for Mountain Daylight Time. Its offset from UTC is UTC-6, 6 hours behind UTC.
MDT is the summer time of the mountain region of the United States and Canada, six hours behind UTC.
In winter these places go back to MST (UTC-7). Arizona does not use MDT. Alberta stopped changing its clocks in 2026 and now stays on UTC-6 all year, so it is no longer an example of MDT.
Where MDT is used
Mountain United States and Canada in summer. The table shows examples, not every place. Entries in bold are on MDT at that moment.
| Place | Mid-January 2026 | Mid-July 2026 | Now |
|---|---|---|---|
| Denver | MST (UTC-7) | MDT (UTC-6) | MST (UTC-7) |
| Boise | MST (UTC-7) | MDT (UTC-6) | MST (UTC-7) |
| Ciudad Juarez | MST (UTC-7) | MDT (UTC-6) | MST (UTC-7) |
See MST, the matching winter time.
Time difference between MDT and other cities
| City | Compared with MDT, now | Changes in the next 12 months |
|---|---|---|
| New York City | 1 hour ahead | Sun 14 Mar 2027, 07:00 UTC: 2 hours ahead |
| Los Angeles | 2 hours behind | Sun 14 Mar 2027, 10:00 UTC: 1 hour behind |
| London | 6 hours ahead | Sun 28 Mar 2027, 01:00 UTC: 7 hours ahead Sun 31 Oct 2027, 01:00 UTC: 6 hours ahead |
| Dubai | 10 hours ahead | No change |
| Mumbai | 11 hours 30 minutes ahead | No change |
| Singapore | 14 hours ahead | No change |
| Tokyo | 15 hours ahead | No change |
| Sydney | 17 hours ahead | Sat 3 Apr 2027, 16:00 UTC: 16 hours ahead Sat 2 Oct 2027, 16:00 UTC: 17 hours ahead |
A gap changes when the two places change their clocks on different dates. Dates are in UTC.
Working hours that overlap with MDT
When it is 09:00 to 17:00 in MDT, where is it also a working day (09:00 to 17:00)? This uses today’s clock settings, so check the meeting planner for weeks when clocks change.
| City | Shared working hours |
|---|---|
| New York City | 09:00 to 16:00 in MDT (10:00 to 17:00 in New York City) |
| Los Angeles | 11:00 to 17:00 in MDT (09:00 to 15:00 in Los Angeles) |
| London | 09:00 to 11:00 in MDT (15:00 to 17:00 in London) |
| Dubai | No shared working hours |
| Mumbai | No shared working hours |
| Singapore | No shared working hours |
| Tokyo | No shared working hours |
| Sydney | 16:00 to 17:00 in MDT (09:00 to 10:00 in Sydney, next day) |