Eastern Time Zone
time zone observing UTC−05:00 during standard time and UTC−04:00 during daylight saving time
The Eastern Time Zone (ET) is a time zone encompassing part or all of 23 states in the eastern United States, parts of central and eastern Canada, some Caribbean islands and the state of Quintana Roo in Mexico. Most areas in the time zone observe daylight saving time and thus alternate between:
Eastern Standard Time (EST), which is five hours behind Coordinated Universal Time (UTC−05:00) and observed during late autumn and winter, and
Eastern Daylight Time (EDT), which is four hours behind Coordinated Universal Time (UTC−04:00) and observed during spring, summer, and early autumn.
Areas in the Eastern Time Zone which do not observe daylight saving time use Eastern Standard Time, which is based on the 75th meridian west of Greenwich. Observation of daylight saving time starts on the second Sunday in March; at 2:00 a.m. EST, clocks are advanced to 3:00 a.m. EDT, creating a 23-hour day. On the first Sunday in November, at 2:00 a.m. EDT, clocks are moved back to 1:00 a.m. EST, which results in a 25-hour day.
The time in this zone is based on the mean solar time of the 75th meridian west of the Royal Observatory, Greenwich.
The public source identifies “Eastern Time Zone” as time zone observing UTC−05:00 during standard time and UTC−04:00 during daylight saving time. This brief keeps that definition visible, then builds a research path around Eastern, Time and Zone.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 19, 2026. The linked authority identifier is Q941023. None of the 0 selected statements returned an explicit reference.
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This entry incorporates text from “Eastern Time Zone” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.