Polymarket vs Kalshi

Neither, categorically. Kalshi offers CFTC-regulated USD trading with strong economics and sports coverage; Polymarket offers zero-fee standard markets and the deepest liquidity on politics and global events. On any single question, the better platform is the one quoting the better all-in price — which changes market by market. That per-question comparison is exactly what this site does.

Yes. Kalshi is a CFTC-regulated designated contract market — a federally regulated exchange where US residents trade in dollars. Its sports event contracts have been challenged by some state regulators, and federal courts have so far largely sided with Kalshi, but that area remains in motion.

Yes — through its US app. After a 2022 CFTC settlement, Polymarket blocked US users for years; it acquired the CFTC-licensed exchange QCEX in 2025 and launched a regulated US app in December 2025, dropping the waitlist in mid-2026. The global crypto platform remains unavailable to US residents, and the US app is excluded in a handful of states.

Polymarket charges no trading fee on standard binary markets — a few product categories carry taker rates — so your costs are mostly the spread and money movement. Kalshi charges a taker fee of 0.07 × price × (1 − price) per contract — about $1.75 per 100 contracts at 50¢, far less near the extremes — with a 75% discount for resting maker orders on eligible markets. A 1–2¢ better sticker price on Kalshi can be erased by the fee near 50¢.

They overlap heavily on major questions — elections, Fed decisions, economic data, big sports and world events — but word and settle them differently. Our matching pipeline links the pairs that genuinely ask the same thing; those validated pairs are what power the live comparison on this page.

Different user bases, different fees, different access frictions, and different resolution rules. The gaps are real but not free money: closing one means paying Kalshi's fee, moving money onto two venues, and carrying the risk that the two contracts settle on subtly different terms.

Yes, and active traders increasingly do — buy where the question is cheap, sell where it's rich, or simply take each position on whichever venue prices it better. The practical hurdle is capital in two systems: USDC on one side, a KYC'd dollar account on the other.

Kalshi offers sports event contracts — federally regulated contracts on game outcomes, which trade like its other markets rather than like a sportsbook bet (you can exit mid-game at the market price). Several state regulators have contested them; federal courts have so far largely let them stand.

Manifold uses play money, which makes it a forecasting community rather than a trading venue — useful signal, no capital at risk. We track it alongside Polymarket and Kalshi; where all three price the same question, the site shows them together.