Daylight Saving Time begins for most of the United States at 2:00 a.m. on the first Sunday of April. Time reverts to standard time at 2:00 a.m. on the last Sunday of October. In the U.S., each time zone switches at a different time.
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On August 8, 2005, President George W. Bush signed the Energy Policy Act of 2005. This Act changed the time change dates for Daylight Saving Time in the U.S.
Beginning in 2007, DST will begin on the second Sunday of March and end the first Sunday of November. The Secretary of Energy will report the impact of this change to Congress. Congress retains the right to revert the Daylight Saving Time back to the 2005 time schedule once the Department of Energy study is complete.