About EST to MST Time
EST covers New York, Toronto, Atlanta, Miami and Boston. MST covers Denver, Salt Lake City, Albuquerque and Calgary.
Working days overlap between 11:00 and 18:00 EST, which is 09:00–16:00 in MST. That window is where calls land without anyone working late.
Both regions use daylight saving, so the gap holds for most of the year — except for the week or two each spring and autumn when they switch on different dates.
How it works
Mountain Time (Denver) is always 2 hours behind of Eastern Time (New York).
- Take the EST time you want to convert.
- Subtract 2 hours.
- Roll the date forward or back if the result crosses midnight.
Neither side changes its clocks relative to the other, so this gap holds all year.
Zone details: EST is −5 in winter and −4 in summer (UTC), MST is −7 in winter and −6 in summer.
Examples
A working day in EST, seen from MST:
| EST | MST |
|---|---|
| 09:00 EST | 07:00 MST |
| 12:00 EST | 10:00 MST |
| 15:00 EST | 13:00 MST |
| 18:00 EST | 16:00 MST |
| 21:00 EST | 19:00 MST |
Meetings usually work best where the two working days overlap. Drag the timeline above to see the overlap for any hour, or use the full time zone converter for any other pair of cities.
EST to MST Time: frequently asked questions
- What is the time difference between EST and MST?
- MST is 2 hours behind EST in standard time (EST is UTC−5, MST is UTC−7). Both zones change clocks on the same US dates, so the 2 hours difference stays the same all year — except in Arizona, which stays on MST year-round.
- What is 9 AM EST in MST?
- 9:00 AM EST is 7:00 AM MST (standard time).
- Where is EST used?
- Eastern Standard Time (UTC−5) is used in the US East Coast (New York, Miami).
- Where is MST used?
- Mountain Standard Time (UTC−7) is used in US Mountain (Denver, Phoenix).