The Memorial Day weekend typically marks the start of the summer vacation season, which for about three-fourths of American workers will mean the possibility of some paid time off.
The United States is the only highly developed nation that doesn't require employers to offer paid vacation time, according to a new report from the Center for Economic and Policy Research, a left-leaning think tank.
The report examined vacation policies in 21 developed countries, including the United States. The researchers found that every country except the U.S. had laws making employers offer between 10 and 30 paid vacation days a year.
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France's laws granted employees the most paid vacation—30 days a year. But several countries actually guarantee workers more total paid time off when mandated paid holidays are added.
Japan and Canada were at the lower end of the list, with laws that require employers to offer 10 paid vacation days.
The researchers found that 77 percent of U.S. workers get paid vacation time. The workers who do receive it get an average of 13 days a year, according to the analysis.
Full-time U.S. workers were much more likely than part-timers to get paid vacation, and higher- wage workers also were considerably more likely than lower-wage ones to have that benefit, according to the report.
In addition, people who worked for large employers were more likely than those who worked for small businesses to get paid time off.
The CEPR report argues that the data are evidence that the U.S. lags other nations in offering workers time off, and is especially tough on low-wage and part-time workers.
John Schmitt, a senior economist with CEPR and one of the authors of the report, said that even when U.S. workers have paid time off available, they don't always take it. Many may feel they don't have enough job security to risk being out for a period even if they are entitled to the time, he said.
"I think what that means is that people get nervous about both asking for time off and taking time off," Schmitt said.
But conservative thinkers counter that vacation is something that employers and employees can work out on their own.
"I don't know of any compelling reason why the government has to decide for people in what way they want to get paid," said Andrew Biggs, a resident scholar at the conservative-leaning American Enterprise Institute.
Schmitt said the data on paid vacation is little changed from the last time he did this same analysis six years ago, despite the weak economy and extremely tough job market of the past few years.
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It may be that employers didn't want to reduce vacation benefits—which tend to be less costly than other benefits, such as health care—at a time when they were laying off staff and asking other workers to assume more duties.
"I think it's something that's difficult to cut back on," he said.
For its analysis, the CEPR used data from the United Nations and the countries themselves. Schmitt said CEPR then used two sets of U.S. government data to create an apples-to-apples comparison.
The analysis excluded some very small European countries, as well as countries whose economies aren't quite as developed as the United States.
By CNBC's Allison Linn