Convert MDT (Mountain Daylight Time) to EDT (Eastern Daylight Time)

Best time to schedule a meeting

Standard 9–5 working hours overlap for 6 hours: 9:00 AM–3:00 PM MDT (11:00 AM–5:00 PM EDT). Schedule meetings inside that window.

MDT to EDT conversion table

About MDT

Mountain Daylight Time (MDT) is UTC−6. It is used in Denver and Salt Lake City from March to November.

Mountain Daylight Time is UTC−6, the summer clock for Denver and Salt Lake City. During those months it coincides with Central Standard Time, which is a genuine source of confusion in a country that spans both: a meeting at "6pm MDT" and one at "6pm CST" are the same instant, but the second is not a time anyone is actually on in summer.

About EDT

Eastern Daylight Time (EDT) is UTC−4. It is used in New York, Toronto, Miami and Atlanta from March to November.

Eastern Daylight Time is UTC−4, the summer clock for New York, Toronto, Miami and Atlanta, running from the second Sunday in March to the first Sunday in November. Those dates are US law and do not match Europe's, which changes on the last Sundays of March and October — so for two weeks in March and one in late October the gap between New York and London is an hour different from its usual five.

Does this gap change with the seasons?

This gap is seasonal. The abbreviations themselves are fixed offsets, but the region on MDT switches to MST (UTC−7) from November to March, and the region on EDT switches to EST (UTC−5) from November to March. So the 2-hour figure on this page is correct for the part of the year when both places are actually on these abbreviations, and changes by an hour outside it.

Because both sides shift, there are also short windows each spring and autumn when one has changed and the other has not — the two regions do not switch on the same date. A recurring meeting set during one of those windows is an hour out for a week or two, which is the most common way this catches people.

This is the reason scheduling systems store an IANA zone such as Region/City rather than an offset or an abbreviation: the zone knows its own rules and the offset does not.

Frequently asked questions