Kalshi vs Polymarket US: which prediction market should you use?

The verdict

Choose Kalshi if you want the longest-running market menu, the most ways to fund an account and the exchange with the longest regulated track record — and you live in a state where its contracts are not blocked. Choose Polymarket US if you trade with limit orders, want a fee schedule you can read in full, or want a fixed sign-up credit with published terms.

On cost alone the two are close to a tie for ordinary taker orders. The deciding factors are usually your state, the markets you want and whether you provide or take liquidity. Both rank in our top two of the best prediction markets, with Kalshi first.

Side by side

Regulation: Kalshi, narrowly

Both are CFTC-designated contract markets, the same legal footing as a futures exchange. Kalshi has held that status since November 2020 and launched to the public in 2021; Polymarket US’s exchange was designated in July 2025 and its app opened in December 2025. Polymarket US also runs its own clearinghouse.

Kalshi takes this factor on track record, not on a difference in regulation. One point of confusion to clear up: Polymarket US is not the global polymarket.com. The offshore site is a separate, crypto-based product restricted for US users — our guide to Polymarket US vs Polymarket explains the difference.

Availability: Polymarket US, with a caveat

Kalshi’s sports contracts are blocked or limited by court order in Massachusetts, Michigan, Nevada, Utah and Washington, and the Washington order also covers politics, entertainment and other non-financial categories. Its position in Ohio and Tennessee became uncertain after the 6th Circuit ruled against it on September 25, 2026.

Polymarket US has fewer documented restrictions, but that partly reflects a gap: its documentation publishes no state list. Third-party reports say it is unavailable in Nevada and blocks Arizona, and that its sports contracts are blocked in Maryland and Michigan; we have not confirmed those reports. Polymarket US wins this factor on the current record, but check the app’s location screen before you rely on it. The state-by-state legal tracker has the dated detail.

Markets: Kalshi, narrowly

Both list sports, politics, economics, weather, culture and crypto, and Polymarket US adds a tech category, so on category count Polymarket US is slightly ahead. Kalshi takes the factor on history and reach: it has listed economics, weather and political contracts since 2021, more than four years before Polymarket US opened its US app, and its markets also reach users through brokers including Robinhood, Webull and Coinbase. Neither exchange publishes comparable liquidity figures, and we have not measured order-book depth on either.

Fees: Polymarket US

Both use the same shape of formula: fee = coefficient × contracts × P × (1 − P), where P is the price in dollars. The fee peaks at 50¢ and falls toward zero near 1¢ and 99¢.

• Kalshi: taker coefficient 0.07, rounded up to the next cent; a 0.0175 maker fee applies on some markets. Kalshi’s help center confirms the fee is based on expected earnings, but its official PDF schedule could not be retrieved, so the coefficients are the widely reported figures (Crypto.com’s official schedule uses the same numbers).
• Polymarket US: taker coefficient 0.0695 and a maker rebate of 0.0125, effective October 1, 2026, with banker’s rounding to the cent. Our news report on the new Polymarket US fee schedule covers what changed from the previous 0.06 rate.

Worked example: buying 100 contracts at 50¢ ($50 of contracts).

• Kalshi taker: 0.07 × 100 × 0.50 × 0.50 = $1.75.
• Polymarket US taker: 0.0695 × 100 × 0.50 × 0.50 = $1.7375, which rounds to $1.74.
• Polymarket US maker: −0.0125 × 100 × 0.25 = −$0.3125, a rebate of about $0.31 paid to you.
• Kalshi maker (on markets that charge it): 0.0175 × 100 × 0.25 = $0.4375, rounded up to $0.44.

At other prices, for 100 contracts:

For takers the difference is a cent or two. For makers it is the difference between paying and being paid, which is why Polymarket US wins this factor.

Funding: Kalshi

Kalshi documents debit cards (with Apple Pay and Google Pay), ACH, wire, crypto, PayPal, Venmo and Cash App. Its card deposits have a $10 minimum, and a 2% processing fee may apply. Polymarket US documents debit card, ACH through Aeropay, Apple Pay, PayPal, Venmo, USDC on iPhone and wire (with a $5,000 wire minimum), with debit and ACH limits of $50,000 a day, and describes withdrawals as free. Both are well covered; Kalshi edges it on the number of methods.

Offers: Polymarket US

Polymarket US publishes a fixed Deposit Incentive — a $25 credit when you deposit $10 or more — plus a refer-a-friend program and deposit-and-trade campaigns capped at $2,000 over the life of an account. Kalshi’s referral program is official, but the amount depends on what your account shows, and credits must be used within 7 days. Polymarket US wins on clarity. Neither credit can be withdrawn as cash; see verified prediction market promos for the full terms.

Legal exposure: Polymarket US, narrowly

Both face state litigation. New York sued Kalshi on July 31, 2026, seeking at least $36 billion, and sued Polymarket US on September 24, 2026. Both are named in suits by Wisconsin, Kentucky, Rhode Island and Baltimore, and Minnesota’s ban is enjoined as to both.

The difference is in results so far. Kalshi has lost in the 9th and 6th Circuits (after winning in the 3rd) and faces court-ordered or court-backed restrictions in five states, though it also won a partial injunction in Illinois on October 2, 2026. Polymarket US has fewer rulings in force against it, largely because its cases are earlier. The Supreme Court petitions could reset the picture for both, so neither platform’s availability is settled.

Choose Kalshi if…

• You want long-running economics and weather contracts alongside sports and politics.
• You want to fund with PayPal, Venmo, Cash App or crypto.
• You live outside the states where its contracts are currently blocked.

Choose Polymarket US if…

• You place resting limit orders and want to earn a maker rebate.
• You want a fee schedule and sign-up credit you can read in full in official documents.
• You are in a state where Kalshi’s sports contracts are blocked — after confirming in the app that Polymarket US is available to you.