Overview
- The United Kingdom shifts from British Summer Time to Greenwich Mean Time at 2 a.m. on Sunday, Oct. 26, with clocks moving back one hour.
- Most of the United States returns to standard time at 2 a.m. on Sunday, Nov. 2, when clocks are set back to 1 a.m. local time.
- The transition effectively moves an hour of daylight from evening to morning, according to NIST.
- Hawaii, most of Arizona and the U.S. territories do not observe Daylight Saving Time, though the Navajo Nation in parts of Arizona does.
- Medical experts warn the change can affect sleep and mood through shifts in serotonin and melatonin, recommending daylight exposure and gradual routine adjustments; efforts to make one time permanent remain stalled after the 2022 Senate‑passed bill failed to clear the House, with President Trump calling the current practice inconvenient and costly.