History of Daylight Saving Time Timeline
Why Americans change their clocks: wartime laws, the failed 1974 year-round trial, candy lobbyists and the 2026 fight in the Senate.
Open interactive timeline
Key events
Franklin's joke about Parisian candles
Benjamin Franklin, then US envoy in France, published a satirical letter in the Journal de Paris suggesting Parisians could save on candles by getting up earlier. He proposed no change to the clocks, so he is a precursor rather than the inventor of daylight saving time.
Railroads create the Day of Two Noons
US railroads replaced local solar times with four continental zones, approved at a Chicago convention in October. The zones had no federal force until 1918.
George Hudson proposes shifting the clocks
New Zealand entomologist George Vernon Hudson presented a paper to the Wellington Philosophical Society proposing a two-hour seasonal shift. It is the first modern proposal for daylight saving time.
William Willett publishes The Waste of Daylight
British builder William Willett, who had the idea on a pre-breakfast ride, proposed moving clocks forward in four 20-minute steps each April, for 80 minutes in all. He lobbied for the idea until his death.
Port Arthur, Ontario, moves its clocks
Port Arthur and neighboring Fort William, now Thunder Bay, became the first places to put daylight saving time into practice, locally rather than nationally. Sources differ on the start date, giving May 1 or July 1.
Germany and Austria-Hungary adopt it nationally
During World War I, Germany and Austria-Hungary became the first nations to adopt daylight saving time, to save fuel. Other European countries quickly followed.
Britain follows three weeks later
The Summer Time Act took effect in the United Kingdom. Protesters are said to have demanded the return of their stolen hour.
Standard Time Act signed
President Wilson signed the law that gave US time zones federal force and introduced daylight saving time as a wartime measure.
First nationwide US daylight saving period
–Americans moved their clocks forward nationally for the first time, for about seven months.
Congress repeals it over Wilson's veto
After the war, opposition led by farmers and rural members of Congress ended national daylight saving time, overriding President Wilson's veto. It became a local option.
New Zealand finally adopts Hudson's idea
After MP Thomas Sidey introduced a bill year after year from 1909, New Zealand's Summer Time Act moved clocks forward an hour, 32 years after Hudson first proposed the idea there.
British Double Summer Time
–Britain advanced its clocks two hours ahead of Greenwich Mean Time in summer during World War II.
War Time: year-round daylight saving
–President Roosevelt instituted year-round daylight saving time, called War Time, for the rest of World War II.
Two decades of clock chaos
–With no federal rule, states and towns chose whether to observe daylight saving time and set their own dates. Broadcasters and transportation companies had to republish schedules whenever a locality changed.
Seven time changes in 35 miles
1960sBefore federal rules, a bus trip of about 35 miles between Moundsville, West Virginia, and Steubenville, Ohio, took passengers through seven changes of time.
Uniform Time Act
President Johnson signed Public Law 89-387, setting one national schedule from the last Sunday in April to the last Sunday in October, while letting states opt out. About 100 million Americans were already observing daylight saving time under varying local rules.
First summer under the national schedule
The Uniform Time Act's schedule took effect on the last Sunday in April.
Arizona opts out
Arizona passed its exemption after observing daylight saving time in 1967. Within the state, the Navajo Nation observes it, while the Hopi Reservation inside Navajo land does not.
Britain tries year-round summer time
–Britain stayed an hour ahead of Greenwich Mean Time all year as a trial. The House of Commons ended the experiment after a free vote.
Congress approves a two-year year-round trial
During the oil embargo, Public Law 93-182, the Emergency Daylight Saving Time Energy Conservation Act, set a two-year trial of year-round daylight saving time.
America tries year-round daylight saving time
–Clocks moved ahead in midwinter and stayed there, giving very late winter sunrises. The trial was planned for two years and ended in under ten months.
Support for year-round time collapses
Public support for year-round daylight saving time fell from 79% to 42% between December and March.
President Ford ends the trial early
Public Law 93-434 returned the country to standard time from October 27, 1974, to February 23, 1975.
Start moves to the first Sunday in April
Public Law 99-359 moved the start from the last Sunday in April to the first, beginning in 1987. The rule lasted through 2006.
Energy Policy Act extends daylight saving time
President George W. Bush signed the law that gave the US today's schedule, from the second Sunday in March to the first Sunday in November, starting in 2007. The change also carried daylight saving time past Halloween.
All of Indiana moves its clocks
The statewide change also gave researchers a natural experiment: one study linked it to about a 1% rise in residential electricity use.
Today's US schedule begins
The first spring change on the second Sunday in March.
Russia moves to permanent daylight saving time
Russia stopped changing its clocks by staying on summer time, and Belarus followed.
Russia reverses to permanent standard time
Three years after adopting permanent summer time, Russia switched to permanent standard time.
First Sunshine Protection Act introduced
Sen. Marco Rubio of Florida introduced a bill for permanent daylight saving time, with a House version from Rep. Vern Buchanan two days later. Both died in committee.
Florida passes its own Sunshine Protection Act
Governor Rick Scott signed a state law for year-round daylight saving time, which can take effect only if Congress authorizes it.
4.6 million Europeans weigh in; 84% want it gone
The European Commission's public consultation drew about 4.6 million responses, the most it had ever received, about 70% of them from Germany. President Juncker said the EU would act on the result.
California voters pass Proposition 7
About 60% of voters let the legislature pursue permanent daylight saving time, pending federal approval. The legislature never acted on it.
European Parliament votes to end clock changes
Parliament voted 410 to 192 to end seasonal changes by 2021. The member states in the Council have not agreed a position, so Europe still changes its clocks.
Fatal crashes rise 6% after the spring change
A University of Colorado Boulder study in Current Biology found about a 6% rise in fatal US crashes in the week after clocks go forward, or about 28 deaths a year. The lead author said the data supports ending the switch, not choosing a side.
Sleep doctors back permanent standard time
The American Academy of Sleep Medicine called for ending seasonal changes in favor of year-round standard time, not daylight saving time. Not all researchers agree the evidence settles the question.
Senate passes permanent daylight saving time
The Senate passed S. 623 by unanimous consent, with no recorded vote. The House never voted on it, and the bill expired with the 117th Congress.
Mexico abolishes it
Mexico ended clock changes after 26 years, except in municipalities along the US border that stay aligned with their neighbors.
Lebanon briefly has two times at once
The caretaker government delayed the clock change for Ramadan. Many businesses, broadcasters and the Maronite Church ignored the decision, and the cabinet reversed it within days.
Trump vows to eliminate daylight saving time
As president-elect, he posted that Republicans would use their best efforts to eliminate it, calling it inconvenient and costly.
Gallup: support falls to 40%
54% of Americans said they wanted to do away with daylight saving time, while 40% favored it. In 1999, 73% had favored it.
Stanford model favors permanent standard time
A PNAS modeling study estimated permanent standard time could prevent about 300,000 strokes and 2.6 million obesity cases, with permanent daylight saving time giving roughly two-thirds of that benefit. The authors noted the limits of their assumptions.
Sen. Cotton objects on the Senate floor
Sen. Tom Cotton of Arkansas blocked a unanimous consent request to advance the bill, the fast-track route used in 2022.
British Columbia makes its last change
The province announced on March 2 that it would stay on its summer clock after the March 8 change, with some regional exceptions.
Alberta passes the Official Time Act
The act received Royal Assent, ending seasonal clock changes in the province.
House passes the Sunshine Protection Act, 308-117
The House passed H.R. 139, which would make daylight saving time permanent, with Trump's backing. The bill went to the Senate.
Orthodox Jewish groups oppose the bill
NPR reported that groups including Agudath Israel and the Orthodox Union opposed it because the morning service cannot begin in the dark, and later winter sunrises would collide with the workday. School boards and some health advocates raised other concerns.
Manitoba ends seasonal changes
Premier Wab Kinew announced that the province would not set its clocks back in November.
Trump posts a number he says is Cotton's
Trump urged people to call a phone number he said was Cotton's. Cotton replied that Congress has repealed permanent daylight saving time before, and that Arkansas children should not go to school in the dark. Sen. John Kennedy called the bill 'dead as disco.'
Clocks fall back anyway
With no Senate vote, most of the US returned to standard time at 2 a.m., on the earliest date the first-Sunday rule allows.
Western Canada stays put
Alberta, Manitoba, most of British Columbia and the Northwest Territories did not set their clocks back, joining Yukon and most of Saskatchewan. This winter they sit an hour ahead of US neighbors that fell back.
42 more in the interactive timeline.
Open interactive timeline