Fifteen percent of American adults have bought contracts on sports prediction markets, a new annual survey finds, placing these relatively new platforms within striking distance of traditional online sportsbooks as a form of leisure spending tied to live sport.
Survey puts participation at one in six adults
The Siena Research Institute (SRI) and St. Bonaventure University’s Jandoli School of Communication released the findings of the yearly American Sports Fanship Survey, which included a new focus on the rise of prediction markets.
Fifteen percent of Americans said they had placed a bet on a sporting event using an online event-based prediction market, such as Polymarket, Kalshi, Crypto.com, or Robinhood.
That figure included 42% of the survey’s most-avid sports fans and 33% of men aged 18 to 49, the most prominent sports betting demographic.
The 15% figure is not far behind the total share of Americans who have an active account with an online sportsbook, which the survey put at 27%.
One in four Americans, and 52% of American men aged 18 to 49, reported having an active account with an online sportsbook such as DraftKings, Caesars, FanDuel, or BetMGM. The survey’s authors framed prediction markets as a distinct but rapidly converging category within the broader leisure landscape of sports fandom.
Young men lead, but the platforms are growing fast
A separate poll published by SSRS on May 28, 2026 offered a narrower but complementary read on current behavior. Five percent of Americans 18 and older say they use prediction markets to make trades on sporting events today, with males aged 18 to 34 the most likely group at 11%, more than twice the national rate.
The gap between the Siena lifetime-use figure of 15% and the SSRS current-use figure of 5% points to a meaningful share of Americans who have tried sports prediction platforms but are not regular participants.
That pattern is consistent with early-stage consumer adoption of any new leisure format.
Combined monthly global trading volume across Polymarket and Kalshi rose from less than $5 billion in September 2025 to about $24 billion by April 2026, according to a Pew Research Center analysis of data from The Block. For comparison, the total amount wagered through legal sportsbooks in the United States averaged around $14 billion per month in 2025.
Sports dominate the platforms’ economics
Sports has made up 80% of total trading volume on Kalshi and 39% on Polymarket since July 2024, according to the Pew Research Center’s May 2026 analysis.
On Kalshi specifically, 87% of March 2026 trading volume, $9.9 billion out of $11.39 billion, came from sports event contracts.
An analysis by the Financial Times found that sports contracts accounted for approximately 90% of Kalshi’s fee revenue. The Financial Times reported that Kalshi generated $1.3 billion in estimated annualized revenue from sports contracts, a figure representing nearly a quarter of DraftKings’ sportsbook revenue, against the company’s 2026 total revenue guidance of $6.5 to $6.9 billion.
Sports event contracts allow users to buy “Yes” and “No” positions associated with different outcomes, offering a product functionally similar to placing a wager at a legal sportsbook.
What the numbers mean for fan behavior
The participation data arrives as sports fandom itself has been shifting toward more financially engaged viewing habits. Researchers studying how social settings shape enjoyment have noted that structured shared experiences, whether watching a game at a bar or tracking a live contract, activate similar bonding and attention mechanisms.
The prediction market format layers a financial stake onto that experience, shaping when and how fans follow sporting events.
Congress is considering regulation of these platforms, while Kalshi and Polymarket have become major advertisers on and partners of professional sports leagues. The regulatory question will help determine whether sports prediction markets consolidate as a mainstream leisure category or remain a niche alongside traditional gambling.
For now, the consumer behavior data suggests a fast-moving shift. Americans who already spend leisure time and money tracking live sport are adopting prediction contracts at rates that mirror other leisure categories that posted sudden double-digit adoption jumps in a single survey cycle.
The platforms’ growth from a niche financial product to a sporting pastime embedded in NFL, NBA, and FIFA viewing has happened, by most measures, in under two years.
