Daylight saving time in 2025, when clocks change by an hour, is starting tonight. Here’s a look at when exactly we “spring forward” and how daylight-saving time works.
What time exactly does the time change for daylight saving 2025?
The time change will take place at 2 a.m. on Sunday, March 9, moving ahead to 3 a.m.
How does the time change work in the spring?
In the spring, the clocks move forward one hour, meaning the sun sets an hour later in the evening and rises an hour later in the morning.
Digital clocks like the ones on cell phones will automatically change. Analog clocks and any clocks or watches that do not automatically adjust will need to be reset manually.
With the change, we lose an hour of sleep.
Medical research has shown this shift is associated with several health concerns, including an uptick in strokes, heart attacks, and traffic accidents in the days following the time change.
When does daylight saving time end in the fall?
Daylight saving time ends this year on Sunday, Nov. 2, when clocks will “fall back” one hour. With that change, the sun will set an hour earlier in the evening and rise an hour earlier in the morning.
Which countries do daylight saving time outside of the U.S.?
Outside the U.S., most of the countries that observe daylight saving time are in Europe, where it’s common, according to the Pew Research Center. France, Italy, Spain, Germany, the United Kingdom and Switzerland are among the countries where it’s practiced.
Daylight saving time is also observed in some parts of Canada and Australia. In Africa, Egypt is the only country to observe it.
Which U.S. states don’t do daylight saving time?
Hawaii and most of the state of Arizona do not observe daylight saving time, according to the Department of Transportation, which oversees time zones in the U.S.
Daylight saving time is also not observed in the U.S. territories of:
- American Samoa
- Guam
- Northern Mariana Islands
- Puerto Rico
- U.S. Virgin Islands
Who invented daylight saving time?
Some have said Benjamin Franklin started the practice in 1784. He wrote a satirical essay for the Journal de Paris proposing regulations to ensure early risers.
Philadelphia’s Franklin Institute, however, disputes the claim and looks to New Zealand entomologist George Hudson, who proposed a two-hour clock rollback in 1895. The suggestion was inspired by his passion for collecting bugs, as he wanted more light after work to gather insects.
Still, others credit British builder William Willet, who wrote a pamphlet in 1907 that encouraged moving clocks forward in the spring so that people could get out of bed earlier. Lighter and longer days were supposed to save energy, reduce the number of traffic accidents, and help people be more active.
In 1916, during World War I, Germany became the first country to practice daylight saving time to conserve fuel, according to the Congressional Research Service. Other European countries soon followed, and the U.S. started practicing daylight saving time in 1918 to add additional daylight hours and help conserve energy.
Today’s practice of starting daylight saving time on the second Sunday in March each year and ending it on the first Sunday in November was enacted under former President George W. Bush.
Do you find yourself thinking about how daylight saving time will impact your sleep?
Some people may experience anxiety just from discussing the time change, as it can completely disrupt their schedule.
At 2 a.m. Sunday, the clocks will fall back one hour, marking the end of the time change known as daylight saving time for most states. Turning the clocks back allows our daylight to shift earlier in the morning.
Prepare now before daylight saving time
How Daylight Saving Time affects our circadian rhythms
Jeffrey Gardere, Certified Clinical Psychologist, discusses how Daylight Saving Time affects our circadian rhythms.
To help ease before Sunday, experts said you should prepare before the time changes.
"We still have a couple of days to change our sleeping habits because, as we know, this is all about the circadian rhythm, and it’s based on a 24-hour basis," psychologist Dr. Jeffrey Gardere said.
As the light and darkness shift, our hormones can also shift.
"It really does throw us off," Gardere adds.
What are the health effects on children?
The effects of time change are not limited to adults. Children in the family will also be impacted by the change.
"They’re going to be thrown off by it, too, and if it throws them off, it’ll throw them off at school where they’re going to be a bit deregulated," Gardere said.
Parents can help their kids adjust to the time changes by improving their nutrition to regulate their bodies more effectively.
"Lighter meals for a few days. That is very important," Gardere said.
When it comes time for bedtime, the TV should not be on because the light will keep them up even later.
"They’re going to be tired much earlier. That we already know," Gardere said.
Health risks and benefits of Daylight Saving Time
Brendan Duffy, Director at Catholic Health Sleep Services, explains Daylight Saving Time's health risks and benefits.
According to Gardere, the ability to put your children or yourself to bed earlier is dependent on how our bodies regulate energy. It is recommended that parents allow their children to discover their own circadian rhythm, as children are quite adaptable.
Perhaps it simply boils down to spending some extra cozy time together, which is beneficial for everyone.
Tell me if this story sounds familiar: A New York City real estate developer ran for office as a Republican, got elected, and did things that profoundly affect every American today. Only his name wasn’t Donald Trump.
Instead, I’m talking about William M. Calder. To be fair, Trump does come into this story eventually, but not until much later.
Calder started it out because it was he who represented New York state in the U.S. Senate from 1917 to 1923, and who championed the idea of adopting daylight savings time in the U.S.
The latest installment of our twice-a-year ritual – spring ahead, fall back – is Sunday. Clocks are set to move ahead from 2 a.m. to 3 a.m. on March 9.
“Very costly to our Nation!”
Calder sponsored the original law in Congress in 1918: the Standard Time Act. Besides setting up daylight savings as a wartime energy-saving measure, it also divided the U.S. into standardized time zones.
The time zone part isn’t controversial, as far as I can find.
But, here we are, fully 107 years later, and despite some starts and stops we’re still following Calder’s clock rules, and despite that a majority of Americans think we should just pick one system – permanent daylight savings time seems to be the most popular idea – and stick with it.
Now, to the other New York real estate developer-turned-politician, President Trump, who has been on the record many times saying he thinks it’s time to stop.
“The Republican Party will use its best efforts to eliminate Daylight Saving Time, which has a small but strong constituency, but shouldn’t!” Trump wrote on Truth Social in December. “Daylight Saving Time is inconvenient, and very costly to our Nation.”
A rare bipartisan issue?
This seems like a very rare bipartisan issue: In 2022 when Joe Biden was president, the Democrat-controlled U.S. Senate passed a bill to keep the U.S. on daylight savings time permanently.
But it didn’t make it through the House, so Biden never got a chance to sign it.
That’s in keeping with the tortured history of this whole idea, which has far more political intrigue and twists and turns than you might think. A few highlights:
The U.S. actually ditched daylight savings time just one year after Calder’s law passed, in 1919. The president at the time, Woodrow Wilson, vetoed the bill to get rid of it, but Congress overrode his veto, something that happens very rarely, 110 times total in the entire history of the U.S.
The U.S. brought it back during World War II, again as a cost-saving measure. After that war, the federal government got out of the daylight savings business, but states and even local communities could and sometimes did observe it.
In 1966, the U.S. brought back the twice-a-year switch. People rebelled, and so in December 1973, Congress agreed to try a two-year experiment: permanent daylight savings time, which is what polls suggest Americans want now.
But, and we should watch out for this, parents especially hated what happened as a result – and Congress ended the experiment just eight months later, ahead of schedule. The big problem: Too many kids going to school in the pitch dark during the dead of winter. Consider that sunrise was 8:27 a.m. in Washington, D.C., on January 7, 1974, for example.
Ever since then, we’ve been back to the daylight-saving switch-a-roo.
Maybe bring in Elon Musk
What will happen? Will Trump make a push to undo the last legacy of his predecessor in the New York real estate-to-politics pipeline? Will we make the switch only to have history repeat itself with people realizing – oh wait, maybe children carrying flashlights to the school bus at 8 a.m. isn’t such a great idea after all?
Will Americans continue the pattern of the past 50 years of debating and griping, but never actually do anything? Trump on Thursday suggested he now thinks it’s more of a “50-50 issue,” so maybe this is the most likely result.
Besides living in the U.S. and thus being affected by this, I’m curious as a student of human nature which result will prevail.
Meantime, maybe Trump can add it to the long list of things he’s given to Elon Musk.
If only he can find the time.