As the cost of college tuition in the U.S. continues to climb, there's pressure on students to do whatever they can to keep up. Traditionally, that's meant taking part-time jobs or selling textbooks and used clothes. But multiple studies find that a growing number of female students are using "sugar daddy" services to supplement their income and pay down tuition.

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A sugar daddy is generally an older, wealthier man who pursues younger, often college-aged students (i.e. "sugar babies") for companionship in exchange for money and a luxurious lifestyle. That's the sales pitch, at least. But sugar babies often report that sex is an unspoken part of the deal, even if online sugar daddy services such as Seeking Arrangement maintain that consensual companionship is the goal.

How popular are sugar daddy services?

In 2013, Seeking Arrangement — "the leading Sugar Daddy dating site where over 5 million members fuel mutually beneficial relationships on their terms," according to its website — reported that 44 percent of its nearly 2 million sugar babies were college students. There is an apparent effort to recruit college students to the site, which offers free premium memberships to those who sign up with a .edu email address. In a recent report, Seeking Arrangement announced that "a quarter of a million" college students in the United Kingdom use the sugar daddy service.

At public schools in the South and private schools in New York, the appeal of using sugar daddies is evidently widespread. The company ranks Georgia State University, New York University, Temple University, the University of Central Florida, and the University of South Florida as its top five "Fastest Growing Sugar Baby Schools," based on sign-up data.

The appeal is obvious: College students who use Seeking Arrangement earn an average of $3,000 per month, the company reports.

Seeking Arrangement reports that 36 percent of the monthly allowance for student sugar babies was spent on tuition and fees, 23 percent on rent, and 20 percent on books in 2015. But it's unclear where that data comes from or how college-aged sugar babies spend their earnings. Anecdotally, members of the site have reported using the money to pay for tuition and one sugar baby told The Atlantic that "the site was extremely popular among college students" and that "tons of girls at Columbia and NYU had profiles to help pay tuition bills."

Seeking Arrangement - seekingarrangement.com

The unspoken truth about sugar daddy services, however, is that sex frequently factors into the equation, leading some experts to conclude that sugar babies are essentially prostitutes.

“[The administrators of Seeking Arrangement] are trying to avoid the negative stigma of prostitution by advertising this as just another dating website, but money is exchanged for arrangements that may include sex," Tammy Castle, a professor at James Madison University who researches escort websites, told The Atlantic.

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ATTN: previously reported on how college students are increasingly turning to sex work to pay the bills. That includes everything from "camming" (charging people to subscribe to online video streams), to modeling, and stripping. There's a range of ways that students are making money on the side in unconventional industries, and using sugar daddies appears to be an increasingly popular option.

"The biggest challenge for student sex workers is related to dealing with the stigmatization and managing secrecy," researchers at Swansea University wrote in a 2015 study. "Safety and dealing with unpleasant clients are also important negative aspects of the work, while having good clients is an important reason for liking the work. Students engaged in direct sex work are in need of more specialized support."

ATTN: is working with Seeking Arrangement for a comment on this story and will include the company's response when one is provided.

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