One of the most intractable, contentious and niche issues in US politics has come back into the spotlight. This week, the US House of Representatives voted to make daylight saving time permanent in the United States.

The Sunshine Protection Act, which the House approved by a bipartisan vote of 308–117, would implement year-round daylight saving time nationwide. This would effectively extend the current eight-month period of daylight saving to cover the four winter months, in which standard time is observed.

Having now passed the House, it will head to the Senate, where it is likely to encounter stiff opposition even from some Republicans.

President Donald Trump promised before his second inauguration to “eliminate” the “inconvenient, and very costly” twice-yearly clock changes.

But it may not be so easy. Debate has raged for decades between sleep scientists and industry groups as to whether the time change should be abolished in favour of year-round standard time (with brighter mornings and darker evenings), or year-round daylight saving time (with darker mornings and brighter evenings).

While it may appear to be an academic choice between the two, they would have radically different impacts on the lives of hundreds of millions of Americans.

Daylight saving’s moment in the sun

The debate over whether or not daylight saving is worth the trouble has progressed little in the past century. Senators as far back as 1919 argued over whether or not the benefits of daylight saving time for urban workers outweighed drawbacks for farmers.

While 64% of Americans want to abolish clock changes, 43% want to see year-round daylight saving time and 28% want to see year-round standard time.

The cost of shifting between the two time zones each year has been estimated to cost the economy over half a billion dollars annually. The time changes cause a rise in heart attacks, car accidents and hospital admissions, though an extra hour of evening daylight can also bring increased leisure time, consumer spending and potential energy savings.

Modern polls consistently show that Americans abhor the inconvenience of the biannual clock change but also that they can’t agree on a permanent solution. According to a YouGov poll in February 2026, while 64% of Americans want to abolish clock changes, 43% want to see year-round daylight saving time and 28% want to see year-round standard time. Almost a third are undecided. In March 2025, Trump himself called it a “50–50 issue.”

During his time in the Senate, Secretary of State Marco Rubio repeatedly introduced the Sunshine Protection Act to make daylight saving time permanent. The Senate surprised many when it passed the act in 2022, though it failed to reach a House vote at the time.

In the past seven years, 19 states have approved similar proposals that would authorise permanent, year-round daylight saving time if permitted by Congress. Proponents of such a system point to possible economic benefits and suggest it could lead to energy savings, lower crime and fewer road accidents.

However, leading sleep research associations such as the American Academy of Sleep Medicine instead support year-round standard time and oppose year-round daylight saving time on the grounds that the increased disconnect between the sun and people’s body clocks in winter would be particularly unhealthy.

Morning in America

Our analysis at the United States Studies Centre in 2024 showed that if clock changes were abolished in favour of year-round daylight saving time, 87% of the contiguous urban US population (around 70% of the total population) would experience sunrise after 8am in winter.

Residents of New York City, Chicago, San Francisco, Philadelphia, Washington DC, Denver and Tampa, among many others, would all see winter sunrises that occur after 8.15am. Indeed, close to half of the over 2,500 urban areas in the contiguous United States would see sunrise after 8.30am on the winter solstice.

Such late sunrise times are currently almost unheard of in the United States. Just 3% of the contiguous urban US population currently experiences sunrises after 8am.

Sunset times would still be no later than 6.30pm in the vast majority of the country at the solstice under year-round daylight saving time, limiting its winter evening benefits.

The misalignment between clocks and circadian rhythms as a result of artificially dark mornings is associated with a host of negative health outcomes, particularly for adolescents.

Given close to 60% of US workers depart for work prior to 8am, the impacts of such late sunrises on a population level would likely be significant. The average school start time of 8am would also mean most children wake, go to school and start class in the dark in winter.

By contrast, year-round standard time would produce brighter mornings and earlier sunsets than under year-round daylight saving time. However, it would sacrifice the popular extra hour of daylight in summer evenings that is produced by switching to daylight saving in summer.

The current daylight saving regime attempts to strike a balance between the two extremes, with standard time used during the darker winter months and daylight saving time used during summer to capitalise on the longer days.

The lack of consensus over whether this flexibility is worth the cost of resetting clocks twice yearly has meant the system has endured, though 16 US states have considered time zone legislation this year alone.

A recurring nightmare

Perhaps most surprising about the concept of year-round daylight saving time is that the United States has already tried it. In 1973, Congress authorised a two-year trial of year-round daylight saving in an attempt to save energy during the global oil crisis.

Yet initial public support for the trial of close to 80% almost halved by the end of the 1973–74 winter amid safety concerns for children and criticisms from the construction and agricultural industries. The trial was abandoned prematurely, and American clocks have changed twice a year ever since.

Lawmakers now find themselves once again navigating a fierce debate between whether to adhere to year-round standard or daylight time. But with Americans so divided on the issue and historical precedent for how quickly support for year-round daylight saving time can collapse, the Senate would do well to take its time deciding whether to make nine in ten urban Americans experience winter sunrises after 8am — or whether permanent standard time would instead help the country to sleep better at night.