TLDR Polymarket and Kalshi together control roughly 79% of the prediction market, with Polymarket leading on volume at $56 billion versus Kalshi’s $44 billion Kalshi is CFTC-regulated and legal for US users, while Polymarket operates offshore on the Polygon blockchain using USDC Kalshi earned $260 million in 2025, driven heavily by sports betting; Polymarket only began charging fees in early 2026 Both Robinhood and Coinbase are building their own CFTC-licensed exchanges, which could threaten Kalshi’s distribution advantage Polymarket acquired prediction market API startup Dome in February 2026, signaling a push to build developer infrastructure
Polymarket and Kalshi have become the two biggest names in prediction markets. Together they control about 79% of a market that has now crossed $127 billion in total notional volume.
They could not be more different in how they operate.
Polymarket runs on the Polygon blockchain and settles trades in USDC. It has no geographic restrictions outside the United States and draws a global, crypto-native user base. Kalshi is a fully regulated US exchange holding a CFTC Designated Contract Market license, the same class of license held by major futures exchanges.
For US residents, that difference is the whole ballgame. Polymarket is blocked for US users following a $1.4 million CFTC fine in 2022. Kalshi is fully legal.
Volume and Revenue
On raw trading volume, Polymarket leads clearly. Its notional volume stands at $56 billion compared to Kalshi’s $44 billion as of February 2026. Monthly trading volume on Polymarket runs above $500 million, while Kalshi sits at roughly $50 to $80 million.
Kalshi, however, is far ahead on revenue. It brought in $260 million in 2025, up from $24 million in 2024. The NFL season alone contributed $138 million in a single quarter. Polymarket had near-zero revenue through most of 2025, only launching