MST to EST Converter
Convert Mountain Time to Eastern Time for any date and time. Eastern is two hours ahead of Mountain — with one famous exception this page handles properly: Arizona, which never changes its clocks.
Convert Mountain Time to Eastern Time
It opens on the current Mountain Time time — pick any date and time to convert it.
Your converted time will appear here.
The MST to EST difference, exactly
The gap, the day change and the offsets — shown with every result.
Two hours for Denver
8:00 AM in Denver is 10:00 AM in New York, in January and July alike.
Three hours for Phoenix in summer
Arizona skips daylight saving: 8:00 AM in Phoenix is 11:00 AM in New York in July.
Date-aware
The converter knows which cities moved their clocks and which did not.
About MST to EST conversion
Mountain Time and Eastern Time are two zones apart, and the headline rule is simple: Eastern is two hours ahead of Mountain. When it is 8:00 AM in Denver, Salt Lake City or Albuquerque, it is 10:00 AM in New York, Toronto and Miami — in winter (MST, UTC-7, against EST, UTC-5) and in summer alike (MDT, UTC-6, against EDT, UTC-4), because both zones change clocks on the same US dates. This converter uses the real time in Denver for Mountain, which keeps the standard rule exact on any date.
Then there is Arizona. Arizona (outside the Navajo Nation) does not observe daylight saving: Phoenix stays on MST (UTC-7) all year. In summer that makes Phoenix three hours behind Eastern, not two — 8:00 AM in Phoenix is 11:00 AM in New York in July, while 8:00 AM in Denver is 10:00 AM. Any converter that gives one answer for “Mountain Time” is wrong for one of those cities half the year. Here, Arizona is its own entry in the zone list: choose Phoenix and you get the Arizona answer, in every season.
Denver on any day of the year (Phoenix matches in winter only):
| MST (Denver) | EST |
|---|---|
| 12:00 AM | 2:00 AM |
| 6:00 AM | 8:00 AM |
| 8:00 AM | 10:00 AM |
| 12:00 PM | 2:00 PM |
| 10:30 PM | 12:30 AM (next day) |
Frequently asked questions
The difference, daylight saving and the cases people trip over.
What is the time difference between MST and EST?
Two hours for most of the Mountain zone: Eastern is two hours ahead (MST is UTC-7, EST is UTC-5), and the gap stays two hours in summer (MDT/EDT). The exception is Arizona in summer — Phoenix stays on MST while Eastern is on EDT, making the gap three hours.
How do I convert MST to EST?
Add two hours — 8:00 AM MST is 10:00 AM EST — unless the Mountain time is in Arizona between March and November, when you add three. This converter handles both: Denver is the default Mountain zone, and Phoenix is in the list.
Why does Arizona not observe daylight saving?
Arizona opted out in 1968, largely because of its desert heat — longer summer evenings meant more air conditioning, not less. The Navajo Nation in the state’s north-east does observe DST, which briefly makes parts of Arizona an hour apart from each other.
Which cities are in MST and EST?
Mountain includes Denver, Salt Lake City, Albuquerque, Boise, Phoenix and Tucson (Arizona on its own rule), plus Calgary and Edmonton in Canada. Eastern includes New York, Toronto, Washington DC, Atlanta, Miami and Boston.
Does the gap ever change for Denver?
No — Denver and the East change clocks on the same dates, so the gap is two hours on every day of the year. Only Arizona’s gap changes, because Arizona never changes.
Is anything I enter stored?
No. The conversion runs entirely in your browser; nothing is uploaded or saved.