Convert Eastern Daylight Time to Mountain Standard Time (EDT to MST)

Understanding EDT and MST Time Zones

Eastern Daylight Time (EDT)

Eastern Daylight Time is observed in undefined and uses the offset UTC-4. Major cities in this time zone include New York, Washington DC, Miami, Atlanta, Boston. This time zone serves a significant global region with important economic and cultural hubs.

Mountain Standard Time (MST)

Mountain Standard Time operates at UTC-7, covering undefined. Key cities include Denver, Phoenix, Salt Lake City, Albuquerque. The 3-hour backward offset from EDT means that when professionals in New York start their workday at 9:00 AM, it is already 6:00 AM in Denver.

EDT is also commonly referred to as Eastern Daylight, Eastern Time, ET, East Coast time, New York time. MST is also known as Mountain Time, MT, Arizona time, Denver time. So if you are searching for Eastern Daylight to Mountain Time, this is the same conversion as EDT to MST.

Complete EDT to MST Conversion Table

The table below shows every two-hour increment converted from Eastern Daylight Time to Mountain Standard Time. Business hours (9 AM – 5 PM) are highlighted for easy scheduling reference.

Times shown in 12-hour and 24-hour format. Last updated 2026-03-09.

Scheduling Between EDT and MST

For business scheduling, the optimal overlap window between EDT and MST falls roughly between 12:00 PM and 5:00 PM EDT. This ensures both New York and Denver teams are within standard working hours.

The small 3-hour gap between EDT and MST means that most of the business day overlaps, making real-time collaboration straightforward. Morning meetings in EDT align well with early morning schedules in MST.

Travel Between New York and Denver

Travelers flying from New York to Denver should adjust their sleep schedule 3 days before departure at a rate of one hour per day. For this time difference, gradual adjustment reduces jet lag dramatically.

Medical experts recommend allowing approximately one day of adjustment per hour of time difference. For the 3-hour shift between EDT and MST, plan for a quick adjustment of 1–2 days.

Daylight Saving Time Considerations

During standard time months (November through March in the US), this offset is fixed. However, if either zone observes daylight saving time, the difference may temporarily shift by one hour during transition weeks in spring and autumn.

For the EDT to MST conversion specifically: EDT (UTC-4) and MST (UTC-7) both observe DST. When both zones transition on different dates, the offset temporarily shifts by one hour for a few weeks. Always verify during March–April and October–November.

Related Time Zone Conversions

References & Resources

• TimeAndDate.com — World Time Zones
• NIST — Official US Time Standard
• IANA Time Zone Database
• Wikipedia — Time Zone Abbreviations
• WorldTimeServer — Current Times Worldwide

Frequently Asked Questions