Americans Wagered Up to $34 Billion on Offshore Prediction Markets

According to a recent study commissioned by the Coalition for Prediction Markets, Americans traded between $11 billion and $34 billion on offshore prediction markets during the 12-month period ending in April 2026. The study, conducted by Harry Crane, a professor at Rutgers and a member of the CFTC Innovation Advisory Committee, suggests that these figures represent a significant proportion of overall U.S. prediction market activity.

Crane's analysis indicates that offshore platforms, which are prohibited from serving U.S. users, account for an estimated 12.5% to 31.5% of all prediction market volume in the U.S. He notes, "Based on current third-party estimates of industry growth, U.S.-based activity on offshore prediction markets could grow to an estimated $133 billion in annual volume by 2030, assuming constant relative market shares of regulated and offshore markets." This projected growth reflects the high demand and participation of U.S. users in these opaque markets.

The study particularly highlights Polymarket, the largest offshore prediction market operator, estimating that approximately $10.6 billion to $26.7 billion of its $55.6 billion trading volume over the past year originated from U.S. users. Despite these users being technically prohibited on the platform, the findings illustrate the considerable challenges regulators face in overseeing such online betting.

Polymarket's operation was impacted in 2022 when the Commodity Futures Trading Commission (CFTC) imposed regulations leading the platform to move its services offshore. Although Polymarket received authorization to operate in the U.S. in 2025, the study points out that the data for trading volumes did not separate U.S. transactions due to reliability issues.

These revelations raise questions about how the U.S. regulatory landscape will adapt to the high volumes of offshore betting and whether existing policies can effectively manage the risks associated with unregulated markets. The implications for both regulatory bodies and user safety remain an ongoing concern as the industry evolves.