Tonight, the U.S. will lose an hour of daylight as it slips into standard time, giving citizens an extra hour of sleep.
Digital clocks will adjust automatically, but analog watches and wall clocks must be set back manually before bed.
The change will shift the U.S. time difference with India from 9 hours 30 minutes to 10 hours 30 minutes behind, affecting international calls and flight schedules.
States that do not observe DST remain on standard time year‑round, including Hawaii, most of Arizona, and U.S. territories such as Puerto Rico and Guam.
The practice began in 1918, was codified in the 1966 Uniform Time Act, and expanded in 2005 and 2007; a 2026 House‑passed Sunshine Protection Act now seeks permanent DST, but the Senate remains silent.
The next change will come on March 14, 2027, when clocks will spring forward to 3 a.m., cutting another hour of sleep for Americans.