Daylight saving time — the twice-a-year ritual of moving the clocks — will end for 2025 on Sunday, Nov. 2, at 2 a.m. local time, when most Americans "fall back" one hour to standard time. The switch delivers an extra hour of sleep but also marks the start of shorter, darker afternoons until the clocks "spring forward" again on Sunday, March 8, 2026. Here is everything you need to know about when the time changes, why daylight saving time exists, and how the adjustment affects your body and daily routine.
When Does the Time Change? Key Dates for 2025 and 2026
In the United States, daylight saving time begins each year on the second Sunday in March and ends on the first Sunday in November. For 2025, DST began on Sunday, March 9, at 2 a.m., when clocks moved forward one hour. It will end on Sunday, Nov. 2, 2025, at 2 a.m. local time, when clocks move back one hour. Looking ahead, DST will begin again on Sunday, March 8, 2026, and end on Sunday, Nov. 1, 2026.
The current schedule has been in place since 2007, when the Energy Policy Act of 2005 extended daylight saving time by roughly a month compared with earlier rules. Before that change, the period typically ran from early April to late October. Other countries follow different schedules: much of Europe, for example, switches to "summer time" on the last Sunday in March and returns to standard time on the last Sunday in October, meaning the U.S. and Europe change clocks on different weekends.
The U.S. Department of Transportation, which oversees daylight saving time and the nation's time zones, points to energy savings, fewer traffic accidents, and reduced crime as benefits of the extended daylight hours — though researchers continue to debate how large those effects actually are.
Why Does Daylight Saving Time Exist in the First Place?
The core idea is straightforward: shift clock time forward by an hour during warmer months so that waking and working hours line up with more natural daylight, reducing the need for artificial lighting in the evening. The concept is often traced to Benjamin Franklin, who wrote a satirical 1784 essay suggesting Parisians could save candle wax by waking earlier. A more direct proposal came from English builder William Willett, who campaigned for what became "British Summer Time" beginning in 1907.
The first place to adopt the practice was Thunder Bay, Canada (then Port Arthur), in 1908. Germany became the first country to implement nationwide daylight saving time on May 1, 1916, during World War I, as a way to conserve fuel for the war effort. The United States followed in 1918 with the Standard Time Act, adopting DST for the same reason: conserving energy during wartime.
Officially, the practice is called "daylight saving time" (with a singular "saving"), though many people say "daylight savings time." The energy-saving rationale that launched DST more than a century ago is now questioned by modern research, which finds that the electricity savings from extended evening daylight are often offset by increased heating and cooling use.
How "Springing Forward" and "Falling Back" Actually Work
The mechanics are simple. In the spring, clocks are set ahead one hour at 2 a.m. local time, meaning that hour is effectively skipped. In the fall, clocks are set back one hour at 2 a.m., meaning that hour is repeated. The mnemonic "spring forward, fall back" helps people remember which direction to move the clock.
Because the change happens at 2 a.m., most people are asleep when it occurs, and internet-connected devices such as smartphones and computers typically adjust automatically. Daylight saving time has not always followed a uniform national schedule. After the U.S. repealed the original 1918 law, the practice became a local matter for decades, leading to widespread confusion as cities and states changed clocks on different dates. Congress re-established DST nationally during World War II — observing it continuously from Feb. 9, 1942, to Sept. 30, 1945, under the name "War Time" — and later standardized the rules with the Uniform Time Act of 1966.
Which States Skip the Time Change — and Why
Not every part of the United States changes its clocks. Arizona (except for the Navajo Nation) and Hawaii do not observe daylight saving time, along with the territories of American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the U.S. Virgin Islands. Arizona's desert heat is a major factor: staying on standard time keeps the hottest part of the day from coinciding with peak afternoon activity. Hawaii's location near the equator means daylight varies little across the year, so shifting the clock offers little benefit.
How the Time Change Affects Your Sleep and Health
The "spring forward" adjustment in March can be surprisingly jarring. Losing an hour of sleep disrupts the body's circadian rhythm, the internal clock that regulates sleep and wakefulness. Research has linked the spring transition to a short-term rise in heart attacks, strokes, and hospital admissions, as well as increases in workplace and traffic incidents in the days immediately after the change.
The American Academy of Sleep Medicine (AASM) has long warned about these risks and argues that permanent standard time — not permanent daylight saving time — is the healthier option, because morning light plays a key role in regulating the body's internal clock. Many sleep experts agree that standard time aligns better with human biology.
The Push to Make Daylight Saving Time Permanent
Changing the clocks has grown increasingly unpopular, and polls consistently show that most Americans want to stop the twice-a-year switch. A bill called the Sunshine Protection Act, which would make daylight saving time permanent nationwide — eliminating the "fall back" — has been repeatedly introduced in Congress. The legislation passed the House in 2025 but has stalled in the Senate, where lawmakers and health experts remain divided.
While many people say they simply want the clock changes to end, sleep researchers caution that permanent DST would leave many regions with very late winter sunrises, which could harm sleep and overall health. For now, the current "spring forward, fall back" schedule remains in place.
The Bottom Line: What to Remember
- Daylight saving time ends Sunday, Nov. 2, 2025, at 2 a.m. local time, and begins again Sunday, March 8, 2026.
- The schedule — second Sunday of March to first Sunday of November — has been in place since 2007.
- DST began as a World War I energy-saving measure in 1916 and was standardized in the U.S. by the Uniform Time Act of 1966.
- Arizona (except the Navajo Nation) and Hawaii, plus several U.S. territories, do not observe DST.
- The Sunshine Protection Act would make DST permanent but remains stalled in the Senate, while sleep experts favor permanent standard time.
