Mountain Standard Time
MST means UTC−07:00 throughout the year. Mountain Time follows regional clock rules and uses UTC−07:00 on your selected date.
Use MT for local civil time →TIME ZONE CONVERTER
MST to MDT
Time Converter
Convert Mountain Standard Time to Mountain Daylight Time. Compare dates, seasonal differences and meeting hours.
MST is 1h behind MDT in 2026.
9 AM MST = 10 AM MDT
Selected date: November 10, 2026. Fixed abbreviations retain their stated UTC offsets.
THE QUICK REFERENCE
CSVMST to MDT conversion table
November 10, 2026 · Date changes are marked.
View the full 24-hour table
| MST | MDT |
|---|---|
| 12:00 AM | 1:00 AM |
| 1:00 AM | 2:00 AM |
| 2:00 AM | 3:00 AM |
| 3:00 AM | 4:00 AM |
| 4:00 AM | 5:00 AM |
| 5:00 AM | 6:00 AM |
| 6:00 AM | 7:00 AM |
| 7:00 AM | 8:00 AM |
| 8:00 AM | 9:00 AM |
| 9:00 AM | 10:00 AM |
| 10:00 AM | 11:00 AM |
| 11:00 AM | 12:00 PM |
| MST | MDT |
|---|---|
| 12:00 PM | 1:00 PM |
| 1:00 PM | 2:00 PM |
| 2:00 PM | 3:00 PM |
| 3:00 PM | 4:00 PM |
| 4:00 PM | 5:00 PM |
| 5:00 PM | 6:00 PM |
| 6:00 PM | 7:00 PM |
| 7:00 PM | 8:00 PM |
| 8:00 PM | 9:00 PM |
| 9:00 PM | 10:00 PM |
| 10:00 PM | 11:00 PM |
| 11:00 PM | 12:00 AM +1 day |
Starting with the MDT working day
These examples start on 2026-11-10 in MDT.
09:00 MDT08:00 →MST · 2026-11-10
17:00 MDT16:00 →MST · 2026-11-10
Which time-zone meaning are we using?
Mountain Daylight Time
MDT means UTC−06:00 throughout the year. Mountain Time follows regional clock rules and uses UTC−07:00 on your selected date.
Use MT for local civil time →ONE CLOCK TIME. THE WHOLE YEAR.
Year CSV09:00 MST to MDT throughout 2026
09:00 in MST converts to 10:00 in MDT on every date in 2026. The destination has the same calendar date.
Every calendar date is included, not just workdays. Date ranges include both endpoints. Based on IANA 2026e; future rules may change.
DON’T LOSE A DAY
When does MST time become a different date in MDT?
Your complete source day: 2026-11-10. Each range shows which destination date to use.
MST · 2026-11-1000:00–23:00UTC−07:00
MDT · 2026-11-1001:00–24:00UTC−06:00 Same date
MST · 2026-11-1023:00–24:00UTC−07:00
MDT · 2026-11-1100:00–01:00UTC−06:00 Next day
Range starts are included; ends are excluded. 24:00 means midnight at the end of that date. Repeated hours appear separately with their UTC offsets. The strip is proportional to elapsed time.
THE BIGGER PICTURE
2026Some things stay in sync.
The difference between MST and MDT stays the same throughout 2026.
JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC
+1h
Neither selected clock changes its UTC offset during 2026.
CLOCK CHANGES
No upcoming clock adjustment
Both selected labels are fixed offsets, so seasonal clock changes do not alter this conversion.
PLAN BEYOND A SINGLE DAY
Daily CSVMST–MDT working hours through 2026
Every date calculated with your working windows. 261 selected MST workdays; public holidays are not applied.
Least shared time7h
Most common7h
Most shared time7h
Days without a 60-min slot0 / 261
A start time that survives the whole year.
Start a 60-minute meeting in MST 09:00–15:00.
These starts fit both working windows on every selected MST workday in 2026, using a 15-minute start grid. The end of each range is the last valid start.
MST: 09:00–17:00, Mon, Tue, Wed, Thu, Fri. MDT: 09:00–17:00, Mon, Tue, Wed, Thu, Fri.
Calculation details and repeated hours
Overnight shifts belong to their start weekday. Host workday means the source calendar date. Repeated local times use the first occurrence.
THE DETAILS THAT MATTER
MST to MDT: useful answers
Is MST / MDT the same as local city time?
MST is fixed at UTC−07:00; MDT is fixed at UTC−06:00. Denver (MT) to Denver (MT) uses regional rules instead. On 2026-11-10, 09:00 at the source becomes 09:00 at the destination (MST). Choose the local-city option above when that is the clock you mean.
Which cities match MST throughout 2026?
Phoenix, United States keep the same UTC−07:00 offset as fixed MST throughout 2026 under the published rules. Matching an offset does not mean every place uses the abbreviation MST.
Which cities match MDT throughout 2026?
Mexico City, Mexico; Guatemala City, Guatemala; Managua, Nicaragua; Tegucigalpa, Honduras keep the same UTC−06:00 offset as fixed MDT throughout 2026 under the published rules. Matching an offset does not mean every place uses the abbreviation MDT.
Does the MST–MDT time difference change in 2026?
The difference stays constant throughout 2026: MDT is 1h ahead compared with MST.
Does this conversion change the calendar date?
09:00 in MST on 2026-11-10 is 10:00 in MDT on 2026-11-10. This selected time stays on the same date in both places. Other times can cross midnight.
Can MST and MDT meet during working hours?
Your selected working windows share 7h on 2026-11-10. The planner above checks the whole meeting duration and shows suitable start times. Edit the windows to match your team.
Related time-zone meanings and conversions
Calculated with IANA 2026e. Working hours are your preferences; public holidays and calendar availability are not included. Our methodology