Congress weighs dueling bills to end twice-yearly clock changes

Sleep physicians warn spring-ahead switch harms health and safety

Clocks across the United States fall back on Sunday, and dueling proposals on Capitol Hill would end the twice-yearly change for good, though in opposite directions. The Sunshine Protection Act, introduced in multiple sessions of Congress, calls for permanent daylight saving time. The Sunshine for Our Kids Act, introduced earlier this year, would return the country to permanent standard time. Lawmakers on both sides of the aisle have supported an end to the clock changes, while splitting over which permanent time to adopt.

Sen. Rick Scott, R-Fla., introduced the Sunshine Protection Act in the Senate. “The American people are sick and tired of changing their clocks twice a year,” Scott said last year when introducing the bill in the Senate Commerce Committee. “It’s confusing, unnecessary and completely outdated.”

Rep. Mary Gay Scanlon, D-Pa., introduced the Sunshine for Our Kids Act in July to push for permanent standard time. “For decades, scientists and medical professionals have highlighted the detrimental mental and physical health impacts of twice-a-year clock changes, particularly on children and teens,” Scanlon said in a statement. “The Sunshine for Our Kids Act will not only help children and teens during the most important years for mental and physical development, but will also promote public health and safety in our communities.”

Neither measure would change how much daylight the country receives; each would shift when that daylight occurs. The two approaches yield sharply different sunrises and sunsets, and the American Academy of Sleep Medicine has taken a position on which is healthier.

Dr. Karin Johnson, a sleep physician and spokesperson for the academy, said the “spring ahead” clock change has been found to have adverse effects on health and safety. “We see more heart attacks, more strokes, more car accidents,” Johnson said. “If we go to a permanent time we would get rid of the harms of that switch.” The academy supports eliminating daylight saving time and adopting permanent standard time, which Johnson said aligns more closely with humans’ circadian rhythms. “In terms of getting rid of daylight saving time completely as opposed to going to permanent daylight saving time, having a more aligned time throughout the year that promotes better sleep and more alignment with our circadian rhythms would really protect our health, our mood and our workplace productivity, our safety on the roads and be much better for our kids,” Johnson said.

Under permanent standard time, the sun would rise and set earlier throughout the year — the latest sunrises and earliest sunsets in winter, the earliest sunrises and latest sunsets in mid-June — and it would always rise before 8 a.m. The estimates come from the websites Daylight Saving Time Explorer, Daylight Impact, and Sunrise-Sunset, which drew on data from the National Oceanic and Atmospheric Administration and are not affiliated with the federal government or any state government or time policy. Times shift by minutes, sometimes a dozen or more, depending on location, and elevation can move sunrise and sunset even within the same time zone. In New York City, the earliest sunrise would be about 4:28 a.m. EST on June 12 and the latest about 7:20 a.m. on Jan. 2, with sunsets between 4:28 p.m. and 7:31 p.m. In Chicago, the earliest sunrise would be 4:15 a.m. CST on June 13 and the latest 7:18 a.m. on Jan. 2, with sunsets between 4:19 p.m. and 7:30 p.m. In Los Angeles, the earliest sunrise would be 4:41 a.m. PST on June 12 and the latest 6:59 a.m. on Jan. 6, with the earliest sunset 4:43 a.m. and the latest 7:08 p.m.

Under permanent daylight saving time, sunrises and sunsets would shift later, with the latest sunset around 8:30 p.m., the sun setting after 8 p.m. more days per year than under permanent standard time, and no days with sunrises before 5 a.m. In parts of the country, the sun would rise after 8 a.m. for dozens of days — in some places more than 100 days. In New York City, sunrise would range from about 5:24 a.m. EDT to 8:20 a.m., with nearly 70 days when the sun rises after 8 a.m., the earliest sunset around 5:28 p.m., and the latest around 8:31 p.m. In Chicago, the range would be roughly 5:15 a.m. CDT to 8:18 a.m., with more than 60 days when the sun rises after 8 a.m., an earliest sunset of 5:19 p.m., and a latest of about 8:30 p.m. In Los Angeles, the latest sunrise would be around 7:59 a.m. PDT and the earliest 5:41 a.m., with the earliest sunset 5:43 p.m. and the latest 8:08 p.m.

Polling shows broad public support for ending the twice-yearly change. In a 2023 survey by the American Academy of Sleep Medicine, more than 60% of respondents said they would support eliminating twice-yearly seasonal time changes — more than 40% said they would “strongly support” it, 22% said they “somewhat support” it, and 26% were neutral. A 2025 Gallup poll also found that most respondents support ending daylight saving time, with sentiment against it growing since the turn of the century.

Permanent standard time is already federally approved, and states may choose it; Arizona, Hawaii, and five U.S. territories already observe it. States that opt out of daylight saving time must observe standard time by default. Johnson said the most practical path to permanent standard time nationwide is state-by-state adoption, but states have held back because they prefer to stay aligned with their neighbors for logistical reasons such as flight schedules.

The United States began experimenting with daylight saving time in 1916 during World War I, adopting it in an attempt to save energy for the war by pushing daylight later into the evening; utility companies reported little savings, if any. Congress repealed it in 1919, and it returned during World War II, enacted by President Franklin D. Roosevelt as “war time” in 1942, before ending again in 1945. A patchwork of state and local policies followed until the Uniform Time Act of 1966 standardized the change dates — the last Sunday in April to “spring ahead” and the last Sunday in October to “fall back.” In 1974, amid the oil crisis, Congress adopted a two-year trial of permanent daylight saving time that lasted only a few months before being repealed; it was poorly received, and lawmakers said it was responsible for traffic accidents, including one in Florida that killed eight children.

Johnson said permanent daylight saving time moves light to the wrong part of the day. “All you do is shift that light to a time that is worse for sleep,” Johnson said. “You really don’t get real benefits of moving light later but you get real harms.” Proponents of permanent standard time also point to schoolchildren, arguing that morning sunlight for trips to school or the bus stop is safer than darkness on dozens of days per year.