Quick Insights

  • Polymarket's monthly trading volume fell 8.9% to $10.2 billion in April, the first month-on-month decline since August 2025.
  • Kalshi's April volume rose 13% to $14.8 billion, extending its lead to a roughly 65% share of global prediction market volume.
  • Total sector volume grew 12.4% to $29.8 billion in April, meaning Polymarket lost share rather than the category cooling.
  • Polymarket retained a clear lead on user count with 678,000 unique April users, more than eight times Kalshi's implied base, indicating Kalshi captures higher-value institutional flow.

Polymarket's monthly trading volume fell 8.9% to $10.2 billion in April, according to Dune Analytics data, the first month-on-month decline the platform has registered since August 2025. The drop is significant less for the absolute numbers than for the comparison: rival Kalshi grew 13% to $14.8 billion in the same month, and the broader prediction market sector expanded 12.4% to $29.8 billion. Polymarket is losing share, not riding a category slowdown.

The Crossover Has Now Played Out

The structural picture is that Kalshi has cemented its position as the global prediction market leader. Year-to-date through 20 April, Kalshi cleared $37.49 billion in notional volume against Polymarket's $29.23 billion. That puts Kalshi at roughly 65% of global market share by volume, an inversion of the 2024 picture when Polymarket commanded roughly 95% of sector activity. Kalshi's $22 billion valuation, set by its Series F in May, now sits $7 billion above Polymarket's $15 billion target.

The reasons trace back to one variable: regulation. Kalshi pursued CFTC designation aggressively from launch and won its election markets lawsuit against the agency in May 2025. That ruling, combined with Robinhood's distribution partnership and an aggressive sports product, gave Kalshi a path into mainstream US retail flow that Polymarket simply could not access while operating offshore. The Third Circuit ruling on 7 April further affirmed federal pre-emption for sports event contracts, removing another obstacle Kalshi had to work around.

Polymarket Still Wins on Users, Just Not on Money

The April data is not uniformly negative for Polymarket. The platform recorded 678,342 unique users in April, more than eight times Kalshi's implied user base, and processed 87.4 million transactions against Kalshi's 94.4 million. Polymarket also collected $29.22 million in fees during the month, against Kalshi's lower fee take from its much larger volume. The implication is that Polymarket retains a deep, active retail user base while Kalshi has captured the higher-value, more institutional flow.

The fee gap also tells a story about platform economics. Kalshi charges a maximum of $0.02 per contract. Polymarket runs a higher take rate that peaks at $1.80 per 100 shares on certain market categories. Higher fees per contract make Polymarket's revenue more resilient than its volume position suggests, but they also make the platform less competitive for high-frequency institutional traders who care most about per-trade cost.

The US Re-Entry Has Not Yet Delivered

The most strategically important development for Polymarket over the past six months has been the launch of its dedicated US app in December 2025, which followed years of forced absence from the US market after the 2022 CFTC settlement. The US product is technically siloed from the global platform's liquidity pool, which has limited its commercial impact. Of Polymarket's $10.2 billion April volume, the US-focused product contributed only $1.26 billion. The remaining $9 billion came from the offshore platform.

The competitive backdrop has also intensified. MoonPay launched Dawn CLI, an AI trading tool for Polymarket, earlier this week. Prophet, another AI-native prediction market platform, launched its first live trading tranche last week with an AI model acting as the counterparty. New entrants are not yet at scale, but they are competing for the same high-engagement retail user base Polymarket has spent five years building.

Regulatory scrutiny has continued to weigh on the sector. Senator Elizabeth Warren and more than 40 Congressional representatives wrote to the CFTC in March demanding action on insider trading concerns. Wisconsin Attorney General Josh Kaul filed lawsuits against Kalshi, Polymarket and other operators in April, alleging violations of state sports betting laws. Whether April's volume decline represents the start of a sustained share loss or a single month of competitive pressure depends largely on how Polymarket's US product scales through the remainder of 2026 and whether the regulatory environment stabilises.

Disclaimer: Nakamoto Daily provides information for educational and entertainment purposes only. Nothing published here constitutes financial, investment, or trading advice. Readers should conduct their own research and consult a qualified financial adviser before making any investment decisions.