Daylight Saving Time to Begin Sunday, March 11, for Most Americans. Most of the nation will return to daylight saving time at 2 a.m. on Sunday, March 11, when clocks will be set ahead one hour, providing an additional hour of daylight in the evening. Under law, daylight saving time is observed from the second Sunday in March to the first Sunday in November, with the nation returning to standard time starting Sunday, Nov. 4. Prior to legislation that took effect in 2007, daylight saving time was observed from the first Sunday in April to the last Sunday in October. Federal law does not require any area to observe daylight time, but those that do must follow the starting and ending dates set by the law. No resetting of clocks is required for those parts of the country not observing daylight time: Arizona, Hawaii, Puerto Rico, the Virgin Islands, American Samoa, Guam and the Northern Marianas. The U.S. Department of Transportation has overseen the time laws since 1966, when Congress transferred this responsibility from the Interstate Commerce Commission.