For one night, there's the prospect of 60 fewer minutes of shut-eye, but ahead are many months with an extra hour of evening sunlight.
The official change was at 2 a.m. local time today.
Not everyone in the U.S. makes the switch from standard time. The exceptions are Hawaii, most of Arizona, Puerto Rico, the Virgin Islands, American Samoa, Guam and the Northern Marianas.
Standard time returns Nov. 6.