How Did We Get A 40-Hour Workweek And Has It Had Its Day?
The Tight-Hour Workday Has Its Roots in The 1860s. But It Didn’t Catch on For Many Decades After That.
— By Andrew Blackman | November 11, 2025
The 9-to-5. Monday blues. Hump day. TGIF. The 40-hour workweek is so firmly embedded in American culture that its norms pepper our language.
But for much of America’s 250-year history, eight-hour work days and five-day workweeks were a pipe dream. The regular workweek consisted of six days, with long hours through the week and sometimes a half day on Saturday. When “overtime” entered the language, it originally just meant more work, not necessarily a higher rate of pay.
So when and how did the 40-hour workweek become the norm? Why has it stuck around so long, and how is the workweek now starting to change amid contemporary developments like remote work, the gig economy and artificial intelligence?
The story begins in Boston, at the close of the Civil War, when machinist Ira Steward penned a pamphlet called “The Eight Hour Movement.” There had been earlier demands for shorter work days, some calling for a reduction to 10 hours, but it was in the 1860s that labor activists like Steward started to rally war-weary workers behind the more ambitious concept of an eight-hour day.
By the 1880s, the movement had gained national attention and a catchy slogan: “Eight hours for work, eight hours for rest, eight hours for what we will.” Large annual parades took place in New York City on the first Monday in September, organized around the theme of the eight-hour workday, and unions staged a national strike for the eight-hour workday in May 1886.
Casting Pig Iron, Iroquois Smelter in Chicago, between 1890 and 1901. Heritage Images/Getty images
However, the U.S. was still decades away from a 40-hour workweek. Working hours around the turn of the 20th century varied widely but were generally much longer than today, says Joseph McCartin, history professor at Georgetown University. Five 10-hour shifts with a six-hour shift on Saturday were common, and steelworkers had it even harder, often working 12-hour shifts seven days a week, with just two days off every couple of weeks. They switched between day and night shifts by working the “long turn,” a single 24-hour shift.
“The long turn was the epitome of how hard the work could be for some workers,” says McCartin. “Working such long hours was dangerous, too—a lot of accidents were attributable to that.”
A New Law—With Exceptions
Over the next few decades, sporadic attempts to shorten working hours continued. In 1916, the federal government passed the Adamson Act, establishing an eight-hour workday for interstate railroad workers, driven largely by union pressure and fear of a shutdown of the rail network as the U.S. was on the cusp of entering World War I.
A Meeting of Railroad Union Leaders in New York in 1916, seen in a clipping from the Goldfield (Nev.) News and Weekly Tribune. Library of Congress
In the 1920s, several individual companies experimented with a 40-hour week, the most high-profile example being Ford Motor. McCartin says the move was driven mostly by concern over high turnover and low productivity. The company found that shorter hours led to fewer accidents, higher productivity and more-loyal workers.
However, the six-day week and long working hours were still the norm, and the prospects for widespread acceptance of the 40-hour workweek remained bleak. “We take it for granted today as something that is natural, but even as late as 1929, a five-day week was still unlikely,” says Ezra Zuckerman Sivan, professor of strategy and entrepreneurship at the Massachusetts Institute of Technology.
Jobless and Homeless Men wait to get free dinner at New York's Municipal Lodging House in the winter of 1932-33 during the Great Depression. Associated Press
The Great Depression changed that, Zuckerman Sivan says. Amid mass unemployment, a bipartisan consensus developed in Washington around work sharing: more people working shorter hours. In 1938, President Franklin D. Roosevelt signed the Fair Labor Standards Act into law. It set a minimum wage of 25 cents an hour and a standard workweek of 44 hours initially, reduced to 40 hours by 1940, with anybody who worked longer hours being entitled to time-and-a-half overtime pay.
“That act really enforced what we think of today as an eight-hour workday and a basic 40-hour workweek,” says Ileen DeVault, professor of labor history at Cornell University’s ILR School.
The story of the 40-hour week doesn’t end there, however. First of all, the Fair Labor Standards Act contained exemptions for certain industries like agriculture, retail and in many cases transportation. It also didn’t apply to executives and other salaried white-collar workers. And women were slower to see the benefits of the new rules, DeVault says, because they were overrepresented in home-based occupations like care for children and the elderly and disabled, which were not covered by the legislation.
Percentage of Employees Who Are Likely/Extremely Likely To Leave Their Current Organization If The Other Organization Offers: *Increasing skills but to stay in current role or next role in career path. †Thirty-two hours instead of 40 hours a week. ‡Forty hours in four days. **Increasing skills to move to a new role that is not part of your current career path. Source: 2023 Gartner Employee Perspectives on the Future of Work Survey
Meanwhile, many employees who were covered by the new rules continued to work longer hours, with overtime pay, especially after the U.S. entered World War II a few years after the legislation.
Employees of Woolworth’s Striking for a 40-Hour Workweek in 1937. New York World-Telegram and The Sun Newspaper Photograph Collection/Library of Congress
In postwar America, the 40-hour week became the norm for millions of workers, with overtime pay acting as a disincentive for employers to require longer hours. There were
even some calls from unions for working hours to be shortened further, but those fizzled out as the labor movement lost ground toward the end of the 20th century. In fact, working hours gradually crept upward from the 1970s onward.
In the new millennium, the U.S. workweek varies widely for different kinds of workers. Email and the internet, laptops and smartphones, and tools like Zoom and Slack have liberated many office workers from the physical office, but at the cost of an increasingly porous boundary between work and home life.
Meanwhile, millions of unionized 9-to-5 jobs have disappeared, leaving many Americans working longer shifts, holding down multiple jobs or picking up ad hoc work in the gig economy. A 2025 Gallup poll found that 40% of full-time employees work 40 hours in a typical week, while 38% work from 41 to 59 and 15% work more than 60 hours a week. Only 8% work less than 40 hours.
“I think a lot of people would say a standard 9-to-5 is a kind of luxury,” says Jennifer Tosti-Kharas, professor of organizational behavior at Babson College.
The Embarcadero Center in San Francisco in March 2022, when the City announced Bloom SF events to lure workers back to offices. David Paul Morris/Bloomberg News
On the other end of the spectrum, a small but growing number of companies are implementing a four-day workweek. Juliet Schor, a sociology professor at Boston College, has spent three years studying more than 200 companies employing a total of more than 8,000 people to assess the impact of the shift to a four-day week.
The results have been positive, she says, for both employers and employees. Employers participating in the trial saw improvements in employee retention, with resignations falling from 1.8 a month before implementing the four-day week to 1.4 a month afterward. Sick and personal days declined from one day per employee a month to 0.8.
For employees, meanwhile, the main benefits were in well-being and work-life balance. “We have 20 well-being metrics, and they all show significant improvements,” Schor says. For example, 69% of participants experienced reduced burnout, nearly 40% were less stressed and anxious, 42% reported better mental health, and 37% percent saw improvements in physical health.
The ideal model, Schor says, is 100-80-100: Employees get 100% of their previous pay for 80% of the work hours, with companies enjoying 100% of the prior output. This depends on productivity improvements and isn’t feasible for every company, Schor says. But even those that don’t see higher productivity can still benefit from happier, more-loyal workers, as Henry Ford discovered a century ago.
American capitalism has grown hand in hand with unions. Here’s how the labor movement shaped how industry operates in the U.S. Photo Illustration: Getty Images/Brian van der Brug/Los Angeles Times
Rep. Mark Takano (D., Calif.) introduced House bills in 2021 and 2023 to shorten the standard workweek from 40 to 32 hours. The bills never came to a vote, but Takano plans to reintroduce the legislation in the current Congress. He says the rise of artificial-intelligence tools gives the idea a broader appeal, along with increased concerns about climate change, since a four-day workweek would mean less commuting.
However, it’s not a foregone conclusion that the productivity gains from AI will usher in the age of 15-hour workweeks and abundant leisure time predicted somewhat prematurely by John Maynard Keynes back in 1930.
For one thing, the gains from AI may not be as spectacular as many anticipate. Many firms are investing heavily in AI to stay competitive but seeing limited productivity gains with today’s tools, says Gartner analyst Emily Rose McRae.
“There are some really big leaps that are necessary in the technology before we are able to use agentic AI to chain together a bunch of different tasks so that a lot of administrative tasks are eliminated,” says McRae. Future AI tools could indeed be truly transformative for working hours, she says, but it’s not guaranteed.
And even if the U.S. workweek does shrink to less than 40 hours in the coming years, what we do with the time may disappoint the dreams of Steward and Keynes.
“We have a culture that glorifies work,” says Tosti-Kharas, pointing to the ethos of hard work at the core of the American dream. “I think even if AI forced us to embrace more leisure time, we would somehow turn it into work.”
— Andrew Blackman is a writer in Serbia 🇷🇸.