It's that time of year again: Many Americans will have to reset their clocks and circadian rhythms when daylight saving time ends on Sunday.
That means, in most states, lighter mornings and darker evenings.
At 2:00 a.m. on Sunday, the time for millions across the country will jump back one hour – an adjustment that has been both welcomed by those seeking extra sleep time or criticized by those who see it as an inconvenience.
Here is what you should know.
How many states observe daylight saving time?
Every U.S. state observes daylight saving time except for Hawaii and Arizona, according to the National Conference of State Legislatures (NCSL). The portion of the Navajo Nation that's in Arizona, however, does observe daylight saving. U.S. territories Guam, Puerto Rico, American Samoa, the Virgin Islands and the Northern Mariana Islands also don't change their clocks.
Many more want to. Nineteen states have enacted legislation that would create daylight saving time for its residents year-round, the NCSL said.
"Because federal law does not currently allow full-time DST, Congress would have to act before states could adopt changes," according to the NCSL.
Many Americans want daylight saving time all year
Only 12% of adults in the U.S. are in favor of the current daylight saving time system, while 47% oppose it, according to an AP-NORC poll released on Thursday.
And 56% of adults polled said they prefer permanent daylight saving time with less light in the morning and more light in the evening, according to the poll. Forty-two percent said they prefer permanent standard time, with more light in the morning and less light in the evening.
Making daylight saving time permanent has failed again
President Trump has urged Congress to pass legislation that would make daylight saving time permanent — which, if enacted, would put an end to the debate over whether to change the time in the U.S. twice a year.
Both the House and Senate should "push hard for more Daylight at the end of a day," the president wrote in April on Truth Social.
But an attempt to stop the time adjustment has once again stalled in Congress.
The Sunshine Protection Act, sponsored by Republican Sen. Rick Scott of Florida with bipartisan support, would make daylight saving time the permanent, standard time. Earlier this week, Republican Sen. Tom Cotton of Arkansas objected to Scott's request to advance the measure using unanimous consent, that a permanent daylight saving time would make winter "a dark and dismal time for millions of Americans."
"By moving the clock back an hour in winter, permanent daylight savings time would push winter sunrises to an absurdly late hour, depriving Americans of morning sunshine that is essential for our safety and well-being," Cotton said Tuesday on the Senate floor.
Former Sen. Marco Rubio, another Florida Republican, previously championed the bill, first introducing it in 2018 and reintroducing it in 2021. The Senate passed the bill in 2022, but it never came to a vote in the House.
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