Stalled legislation
In late October 2025, US Senator Tom Cotton of Arkansas blocked a bipartisan effort to make daylight saving time permanent in the United States by objecting to a request for unanimous consent to advance the “Sunshine Protection Act” for consideration by the other body of congress and send it to the President for signatur4.
The bill, championed by Senator Rick Scott of Florida, aims to end the biannual clock changes and keep daylight saving time in effect year-round, a proposal also supported by President Trump.
“Not every human problem has a legislative solution”, explained Cotton as a somewhat puzzling part of a statement that otherwise emphasized that permanent daylight saving time would result in darker winter mornings, making winter “a dark and dismal time for millions of Americans,”
His objection and the peculiar rules that allow a single senator to block legislation, effectively stalls the bill’s immediate passage, thus solidifying the continuation of the current practice of biannual clock changes. Confusingly, current US federal law permits states to adopt permanent standard time but prohibits them from implementing permanent daylight saving time independently.
A German initiative
The concept of daylight saving time (DST) has roots in the 18th century, with Benjamin Franklin proposing a form of time adjustment in 1784 for Paris to save on candle usage by utilizing morning daylight more effectively.
The idea was later revived by George Bernard Hudson in New Zealand and William Willett in the UK, who advocated for shifting clocks to extend evening daylight.
None of these early ideas were realized until DST was first implemented on a national scale during World War I, when Germany began observing it in 1916 with the explicit aim to conserve fuel. This was followed by the UK and the United States.
The US enacted the Standard Time Act in 1918, establishing DST to begin on March 31, 1918, but it was repealed in 1919 due to public opposition, particularly from farmers who disliked the disruption to their schedules.
The Uniform Time Act of 1966 standardized the start and end dates of DST across the US. This was later modified in 1986 and again in 2007 for the DST to begin on the second Sunday in March and end on the first Sunday in November.
A trial of year-round DST occurred in the US from January 1974 to April 1975 during the oil embargo, but it was abandoned due to public backlash, particularly over children commuting in morning darkness and increased morning accidents.
Today 48 US states observe the switch to DST. Hawaii, Arizona (except the Navajo Nation), and several US territories do not, due to geographic and climatic factors.
As of 2023, around 34 percent of the world’s countries switch to DST during the summer, primarily in Europe and North America
What does science say?
There’s ample, but not altogether conclusive, research on the topic.
The most problematic part science is in agreement of is the action of the twice a year clock switch. There is disagreement about whether the permanent timezone in the US should be standard or daylight saving if the switch is abolished.
Several studies, focussing on the switch itself, have found that the human body has difficulty adjusting its internal clock that governs a lot of when and how different human biology works. The period after each switch sees a slightly higher number of health problems.
While saving candles or fuel was originally the reason for introduction of DST, the US Department of Energy released a report in October 2008 to challenge that. It found nationwide electricity savings of 0.03% for the year 2007. These savings are no longer seen as substantial enough to warrant the switcheroo.
Multiple scientific societies, such as the American Medical Association, Sleep Research Society, American Academy of Sleep Medicine, Society for Research on Biological Rhythms, and National Sleep Foundation have all released statements in favor of a permanent time policy and all recommend to return to permanent standard time.
At the time the release of these statements, most supporting research had focused on the acute consequences of switching time policies. Notably, studies found increases in traffic accidents and cardiovascular events as well as decreased vigilance and workplace engagement, primarily during the “spring ahead” transition. However, there was little work examining the long-term consequences of time policy or the magnitude of impact, all of which factor into policy decisions.
Permanent daylight savings time
Some research concludes that permanent daylight saving time would result in too dark winter mornings, making winter particularly affecting schoolchildren going to school in the morning and working adults who would start their days in darkness. In parts of the US, the sun would not rise until after 8:00 a.m., or even 8:30 a.m., during the winter months.
The main argument for introducing year-round DST is that the lifestyles and work patterns of modern-day citizens are no longer compatible with the concept of shifting the clock every spring and fall and that DST is the better compromise when selecting a single clock time.
Nineteen US states have enacted legislation to adopt year-round daylight saving time
Permanent standard time
There’s research that finds that the number of deers killed by cars during standard time in the US is substantially higher compared to daylight savings time. During standard time commuters drive in the emerging darkness right at the same time the deers are active.
Researchers at Stanford concluded in 2025 that switching to permanent Standard Time could reduce cases of obesity by 2.6 million cases and stroke by 300,000 cases, in reference to the biological timekeeping.
Public opinion, legislation
Retailing, sports, and tourism interests have historically favored daylight saving, while agricultural and evening-entertainment interests and some religious groups have opposed it.
As of November 2025, state legislatures across the United States have considered over 750 bills and resolutions aimed at ending the biannual clock changes associated with daylight saving time, according to the National Conference of State Legislatures. Nineteen US states have enacted legislation to adopt year-round daylight saving time, pending Congressional approval.
US public opinion remains divided, with a Gallup poll indicating about half of Americans prefer permanent standard time, while 24% favor permanent daylight saving time. Health experts mainly support permanent standard time as better aligned with human circadian rhythms.
Outside the US, in Europe the European Commission proposed in September 2018 to end seasonal clock changes as of 2019. Member states would have the option of observing either daylight saving time all year round or standard time all year round. Like in the US, that proposal has stalled as the Commission considers that the onus is on the Member States to find a common position. As a result, progress on the issue is effectively blocked.
A referendum on the introduction of daylight saving took place in Queensland, Australia, in 1992, after a three-year trial of daylight saving. It was defeated with a 54.5% “no” vote, with regional and rural areas strongly opposed, and those in the metropolitan southeast in favor.
Russia switched to permanent DST from 2011 to 2014, but the move proved unpopular because of the extremely late winter sunrises; in 2014, Russia switched permanently back to standard time.
Of all the countries in the world around 34% switch to daylight saving during summer.
The way out of this dilemma
The push for permanent timezones is driven by concerns over disrupted sleep patterns, public health risks linked to time changes, and the inconvenience of changing clocks twice a year.
Reviewing the science, it appears the primary harmful aspect of DST is the actual switching of the clock twice a year and the difficulty human bodies have to adjust their biological clocks.
Perhaps the line that the European commission took points to the way forward for the US. Abolish the switcheroo, join the majority of the world’s countries and let science advice the individual states in choosing which permanent timezone they should adopt.