When Does Daylight Savings End: Millions Lose an Hour and Face Later Evenings
Millions of Americans lost an hour of sleep and will see daylight pushed into the evening, affecting commuters, businesses and early-morning routines. Sunday at 2 a. m. ET the clocks jumped ahead for the start of daylight saving time, and questions about When Does Daylight Savings End are already shaping state legislation and federal debate.
When Does Daylight Savings End: National Institute of Standards and Technology Counts a 238-Day Stretch
People across the country will live under daylight saving time for 238 days this year, the National Institute of Standards and Technology has outlined. That span begins with the spring shift and stretches until the first Sunday in November, compressing mornings and extending usable daylight into the evening for most locations.
In Boston, for example, sunrise moved from 6: 09 a. m. to 7: 08 a. m. and sunset from 5: 41 p. m. to 6: 42 p. m. on the day the clocks sprang forward, illustrating how the shift reallocates an hour from morning to evening.
How the U. S. Naval Observatory and State Laws Set the Clock Change
The start date for daylight saving time has been the second Sunday of March since 2007, a practice the U. S. Naval Observatory identifies as the current schedule used for federal timekeeping. This year the change took effect on March 8 at 2 a. m. local time, creating a 23-hour day for most of the U. S.
At least 19 states have passed laws that would keep them on daylight saving time year-round if the federal government permits that change, underscoring a split between state-level action and federal authority over time standards. Past federal adjustments show the start date has shifted before — from April and earlier experimental periods — reflecting a long history of congressional decisions on time policy.
Who Remains Outside the Shift: Hawaii, Arizona and U. S. Territories
Not all jurisdictions move their clocks. Hawaii and Arizona do not observe daylight saving time, with the Navajo Nation in northeastern Arizona making an exception by observing the change within that area. The territories of American Samoa, Guam, the Northern Mariana Islands, Puerto Rico and the U. S. Virgin Islands also do not change their clocks.
Energy and health effects have been part of the debate: after the 2007 start-date change, the Energy Department found electricity consumption fell by 0. 03%, while other analyses have tied clock shifts to short-term negative health impacts. Those mixed outcomes help explain why opinions remain sharply divided over whether to stop changing clocks twice a year.
For now, the next confirmed time change for most Americans is the return to standard time at 2 a. m. ET on Nov. 1; if federal law is changed to allow states to remain on daylight saving time, states that have passed measures to stay on it could avoid that rollback.
