In 1967, Baby Boomers had the Summer of Love. Two years later, the Summer of '69. Gen X New Yorkers lived through the Summer of Sam in 1977. This year, Gen Z had a Summer of Sports Betting.

Researchers from Bank of America found that 88% of online bettors in July were Gen Zers and Millennials, a group that covers adults born after 1978.

"Notably, until June, Millennials accounted for a larger share of activity, suggesting Gen Z initiated a turning point in the composition of online bettors this summer," the researchers wrote in a note published last week.

The researchers specifically called out the FIFA World Cup as a source of the betting boom. Barron's reported in June that the World Cup was likely to drive new customers to the U.S. sports betting industry.

Findings in the research note were compiled using Bank of America customer spending data and through a survey conducted by the bank in March of 2,351 respondents.

According to the survey, 20% of respondents consider sports betting to be "nontraditional" investing, and Gen Z is twice as likely to believe so. Among all respondents, "buying event contracts on prediction markets was more likely to be considered an investment than sports betting."

But if sports betting is an investment, Bank of America found it's a losing one.

"Customers typically recover less than 75 cents for every dollar transferred to online betting platforms," the research note says.

Gambling participation has a significant impact on account balances, the researchers found: In 2026, the median deposit account balance of those who participated in online betting was 59% of those who didn't bet.

The changing attitudes toward gambling and investing shouldn't be blamed on Gen Z, however, according to Isaac Rose-Berman, a policy fellow at the American Institute for Boys and Men whose work focuses on gambling.

"This is all tied to a rise in financial nihilism, where young people today feel they need to gamble and strike it rich to get ahead," Rose-Berman says. "We should spend less time criticizing Gen Zers for gambling and more time criticizing the people and companies that have spent billions of dollars conflating gambling and investing."

He points out that on some digital brokerage platforms, prediction markets sit alongside typical stock investing and saving accounts, allowing investors to take funds from something as low risk as U.S. government bondholdings and load up on positions tied to the outcomes of sporting events.

"My grandfather lost a lot of money gambling, but he was still able to save for retirement because those accounts and activities were siloed," Rose-Berman says. "If he were alive today and could instantly sell his stocks to bet on the NFL, he would have made far more bad financial decisions."