Permanent Daylight Saving Time Means 2 Billion More Dark School Commutes, Study Estimates

TUESDAY, Nov. 3, 2026 (HealthDay News) — U.S. children and teens would trudge to school in the pitch-black early morning an extra 2 billion times each year if the nation adopts permanent Daylight Saving Time, a new study says.

Ending each year’s “fall back” switch to Standard Time would impose an estimated 2.14 billion additional dark-morning commutes for schoolkids across the United States, the study team found.

The findings were published Oct. 29 in the journal Current Biology.

The U.S. House of Representatives has passed a bill that would make Daylight Saving Time (DST) permanent, but the bill is stalled in the Senate, researchers noted.

"It's called the 'Sunshine Protection Act' because you get an extra hour of light at the end of the day. But you will take that hour from the morning. You could call it the Sunshine Destruction Act," said senior author Horacio de la Iglesia, a professor of biology at the University of Washington in Seattle.

"These dark mornings will inequitably affect children who have to go to school at a certain time,” de la Iglesia said in a news release. “It's a very tangible metric that anybody from any state or socioeconomic background can relate to. Nobody wants their kids to go to school in the dark."

Permanent DST would lead to darker mornings between November to March, when Standard Time currently takes effect, researchers said.

For the new study, researchers calculated how many days each child would be commuting to school in the dark, based on school start times, enrollment data and exact community locations.

The team started first with 14 states that have preapproved a switch to permanent DST — Washington, Oregon, Idaho, Utah, Colorado, Wyoming, Oklahoma, Louisiana, Tennessee, Mississippi, Alabama, Georgia, Maine and Delaware.

In total, there would be 356 million additional dark-morning commutes for kids in those 14 states, with all states seeing an increase, the study said. Georgia would have it the worst, with 71 million more trips to school in the dark under permanent DST.

Extrapolating these estimates across the United States, nationwide permanent DST would result in 2.14 billion extra school commutes in the dark, researchers said.

"For the estimation, we assumed students would be leaving home around 8 a.m.," lead researcher Guadalupe Rodriguez Ferrante, a University of Washington postdoctoral scholar in biology, said in a news release. "That's pretty late, so our calculation is likely an underestimation of the real number."

Communities on the western edge of their time zones would be hardest hit by a change to permanent DST, as well as places with early school start times, researchers said.

For example, Mississippi and Alabama schools have an average start time of earlier than 8 a.m., and both states would see an increase from about 2 million dark morning commutes to more than 20 million each.

"Some districts probably never experience a dark commute under the current system, and, if this passes, suddenly they will wake up to this new reality that their kids are going to school in the dark," Rodriguez Ferrante said. "Keep in mind that we used the actual start time listed for each school, and a lot of schools offer breakfast or other things before school, so the kids could be getting there even earlier.”

Gearing up for school in the dark would cost kids the natural boost that morning sunlight provides their brains and bodies, researchers said.

"When we send kids to school in the dark, we are depriving them from an opportunity to get that morning daylight,” Rodriguez Ferrante said.

A switch to permanent DST also would undo the benefits of having delayed start times for high school students, which are intended to account for teens’ shifted body clocks compared to those of kids and adults, researchers said.

"I've heard the argument, 'If we're in permanent DST, we can just delay the school start time to address these issues,' " de la Iglesia said. "Well, if we do that, you will end up going to work later. And everything is going to get delayed. You will get out of work an hour later, and you will miss the opportunity to enjoy your evening light. And essentially, we're just going to be realigning everybody to solar time. That, by definition, is Standard Time."

More information

Harvard Medical School has more on the health effects of the switch to Daylight Saving Time.

SOURCES: University of Washington, news release, Oct. 29, 2026; Current Biology, Oct. 29, 2026