Monthly trading volume on the Polymarket prediction market experienced a decline of approximately 8.9% in April, marking the first decrease in month-to-month activity since August. According to Cointelegraph, this drop comes as competitors like Kalshi are expanding their market share. Data from Dune Analytics reveals that Polymarket and its U.S.-based trading application collectively generated over $10.2 billion in volume in April, down from more than $11.2 billion in March. Meanwhile, Kalshi's trading volume surged by about 13% in April, reaching approximately $14.8 billion. Overall, the total monthly trading volume for prediction markets increased to around $29.8 billion in April, up from about $26.5 billion in March, representing a 12.4% increase.
Polymarket's decline in volume coincides with the company's efforts to reintegrate into U.S. markets amid heightened legal and regulatory scrutiny from U.S. lawmakers. This scrutiny follows the sector's rapid growth during the 2024 elections. Prediction markets are attracting new competitors, such as Prophet, an AI-native prediction market platform, which recently launched its first live trading tranche. This system features an AI model acting as the counterparty using real capital. Additionally, financial technology company MoonPay introduced an AI technology tool for trading strategies on prediction markets.
Polymarket is actively seeking to expand its presence in the U.S. after exiting in 2022 due to a settlement with the U.S. Commodity Futures Trading Commission (CFTC). This settlement barred the platform from allowing U.S. residents on its main global exchange. In December 2025, Polymarket launched a dedicated app for U.S. customers, although it remains separate from the global platform and its liquidity. Concerns about insider trading on prediction markets, particularly in areas related to war, energy prices, and geopolitically sensitive issues, have been raised by several U.S. lawmakers and regulatory officials.
In March, Senator Elizabeth Warren and over 40 Congressional representatives urged the CFTC to prohibit government insiders from using prediction market platforms for profit while in office or serving in an official capacity. The CFTC asserts that event contracts are a type of swap under its jurisdiction and emphasizes the need for federal employees to understand existing restrictions on prediction market insider trading. Additionally, Wisconsin Attorney General Josh Kaul filed lawsuits against Kalshi, Polymarket, and other prediction markets in April, accusing them of violating state sports betting laws.