Polymarket combines regulation and liquidity

Polymarket’s U.S. re entry matters because it turns the category’s old tradeoff into a direct product advantage. Kalshi proved that a federally regulated prediction market can legally reach U.S. users through brokerages and FCMs. Polymarket proved that crypto rails, open APIs, and lower fees can pull in deeper global trading activity. Putting those together means a U.S. user can get legal access without giving up tight spreads, visible depth, and cheaper trading economics.1 2 3 4 5

• The practical difference is in the plumbing. Kalshi runs a regulated, closed database and built KYC, AML, surveillance, and clearing inside the U.S. system. Polymarket wrote every trade to chain, settled in USDC, and grew faster internationally because builders, market makers, and traders could plug into it more easily.1 2 3
• The liquidity edge is not just more users, it is more usable order books. Infrastructure players already match equivalent Kalshi and Polymarket contracts and route to the best price, which shows how much overlap exists across venues. When the same sports contract can pull depth from a broader trader base, spreads tighten and larger orders clear with less slippage.2 3
• The fee gap changes how the market scales. In late 2025 Polymarket planned U.S. pricing around 0.01% versus roughly 1% effective take at Kalshi. By mid 2026, Polymarket was still monetizing more lightly, around 0.3% blended take versus Kalshi around 1.2%, which helps explain why Polymarket can use lower pricing as a wedge while Kalshi earns more per dollar traded.1 4 5

Going forward, the winners are likely to look less like standalone apps and more like liquidity networks. Regulation opens the door, but the bigger prize is becoming the venue that brokers, consumer apps, and trading tools route into by default. If Polymarket can keep U.S. compliance while preserving its lower cost and broader liquidity model, it becomes the clearest threat to Kalshi’s home market lead.2 4 5