<P> Eastern Daylight Time (EDT), when observing daylight saving time DST (spring / summer) is 4 hours behind Coordinated Universal Time (UTC − 04: 00). </P> <P> In the northern parts of the time zone, on the second Sunday in March, at 2: 00 a.m. EST, clocks are advanced to 3: 00 a.m. EDT leaving a one - hour "gap". On the first Sunday in November, at 2: 00 a.m. EDT, clocks are moved back to 1: 00 a.m. EST, thus "duplicating" one hour . Southern parts of the zone (Panama and the Caribbean) do not observe daylight saving time . </P> <P> The boundaries of the Eastern Time Zone have moved westward since the Interstate Commerce Commission took over time - zone management from railroads in 1938 . For example, the easternmost and northernmost counties in Kentucky were added to the zone in the 1940s, and in 1961 most of the state went Eastern . In 2000, Wayne County, on the Tennessee border, switched from Central to Eastern . In March 2018, the Florida Legislature passed a bill requesting authorization from Congress for year - round daylight savings time, which would effectively put Florida on Atlantic Standard Time year - round . </P> <P> The Uniform Time Act of 1966 ruled that daylight saving time would run from the last Sunday of April until the last Sunday in October in the United States . The act was amended to make the first Sunday in April the beginning of daylight saving time as of 1987 . The Energy Policy Act of 2005 extended daylight saving time in the United States beginning in 2007 . So local times change at 2: 00 a.m. EST to 3: 00 a.m. EDT on the second Sunday in March and return at 2: 00 a.m. EDT to 1: 00 a.m. EST on the first Sunday in November . In Canada, the time changes as it does in the United States . </P>

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