Daylight Saving Time begins early Sunday: clocks move ahead, sleep and safety concerns return
daylight saving time starts early Sunday morning, and the immediate change is simple: turn clocks ahead one hour Saturday night. The shift is arriving this weekend across most of the United States, with many devices expected to update automatically. The reason it matters is not just the lost hour of sleep, but the documented health and safety risks that can follow the spring change.
What happens this weekend, and who is affected
In the United States, daylight saving time begins in the early morning hours on Sunday, with clocks set forward one hour at 2 a. m. local time. The practical effect is that most people lose an hour of sleep and see later sunrises and sunsets through the period that ends when clocks are set back one hour in November.
Not every U. S. state observes the shift. Hawaii and most of Arizona do not observe daylight saving time, with the exception of the Navajo Nation. Several U. S. territories also do not observe it: American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the Virgin Islands.
Health and safety warnings, plus what you can do now
Dr. Keisha Sullivan, a sleep medicine physician at Kaiser Permanente, warned that the spring change can come with measurable downsides. “Research does show that during or following that spring change, we are at an increased risk of heart attacks, ” Sullivan said. She added that people may notice they are not focusing as well.
Safety concerns extend beyond the bedroom. Numerous studies, including one by the University of Colorado Boulder, show the time change leads to an increase in deadly car accidents.
Sullivan said small adjustments ahead of time can make the transition easier. “Go to bed earlier by 15 minutes each day, ” she said, calling preplanning “the key. ” She also advised avoiding caffeine at least six hours before bedtime and avoiding screen time and electronics one to two hours before lights out. After waking up, she recommended spending time outside, explaining that sunlight exposure suppresses melatonin and helps people stay awake and alert.
More broadly, Sullivan said it is best to go to bed and wake up at the same time every day, even on weekends. She also cautioned that not getting enough sleep can contribute to memory issues, weight gain, and food cravings.
Daylight Saving Time debate and the broader policy picture
Daylight Saving Time remains controversial, and the argument is no longer just about convenience. Some lawmakers want to end the practice of changing clocks entirely, while proposals at different levels of government push for either permanent standard time or permanent daylight saving time.
At the federal level, the House of Representatives and the Senate have versions of the Sunshine Protection Act, seeking to make daylight saving time permanent nationwide. The legislation was reintroduced in January 2025 in the 119th Congress and remains stalled in congressional committees.
Outside the U. S., participation varies widely. In North America, much of Canada and parts of Mexico near the U. S. border participate. British Columbia Premier David Eby announced Monday that the province is switching to permanent daylight time and that the new time zone will be called “Pacific Time. ”
What’s next
In the hours leading into early Sunday morning, the most immediate next step is preparation: adjust schedules gradually, limit caffeine and screens before bed, and plan for reduced alertness after the clock change. For lawmakers, the next development to watch is whether federal proposals that would lock in a single national approach move out of committee. For now, the reality is fixed for this weekend: daylight saving time arrives with a one-hour jump, and the push to reduce its disruption continues in the background.
