Kalshi is challenging Polymarket’s reported trading activity as both prediction market platforms fight for market leadership.
Kalshi’s head of crypto, John Wang, said March volume comparisons were misleading because they failed to separate platform structure, market categories, and possible artificial activity.
The dispute comes as prediction markets face sharper scrutiny from regulators, prosecutors, and political figures.
Kalshi Disputes March Volume Estimates
Wang said Kalshi processed about $13 billion in March, while Polymarket handled closer to $10 billion. His comments pushed back against estimates that placed both platforms near $12 billion during the same period.
He argued that simple volume comparisons ignore how each market operates. Kalshi draws heavy activity from United States sports contracts, while Polymarket attracts broader global volume through on-chain markets.
He also said Polymarket’s war-related contracts form a large part of its political activity, yet Kalshi does not offer the same category.
Wash Trading Claims Raise Data Concerns
Wang also claimed that wash trading may account for as much as 70% of activity in some of Polymarket’s top markets. The claim remains unverified, and public blockchain data does not provide a final answer on the scale of possible artificial trades.
Another Kalshi-linked figure supported the criticism and cited Dune dashboard data that placed Polymarket’s March volume near $9.5 billion.
That estimate remains below Kalshi’s stated $13 billion figure and adds more pressure to the public debate over reliable prediction market data.
As of April 2026, Kalshi appears to have moved ahead in year-to-date notional volume. Reported figures place Kalshi near $37.5 billion, while Polymarket stands at around $29.2 billion.
Prediction Markets Face Wider Scrutiny
The volume dispute comes during a tense period for the sector. United States prosecutors reportedly charged Gannon Ken Van Dyke with using classified intelligence to place Polymarket bets tied to the capture of Nicolás Maduro. Authorities allege the trades generated more than $400,000 in profit.
Kalshi also disclosed that it had fined and suspended three congressional candidates for betting on their own races. The cases have renewed concerns over insider access, market fairness, and event contract oversight.
Regulatory pressure is also rising abroad. Brazil’s central bank has moved to block prediction markets, citing risks to investor protection and market integrity.
In the United States, criticism has become more direct. Donald Trump said he was “not happy” with prediction markets and described them as “somewhat of a casino.” Meanwhile, the CFTC began a formal process on March 12, 2026, to examine how event contracts should be classified under federal rules.
