Kalshi vs Polymarket US: how the two exchanges differ

This is general information, not legal advice.

Kalshi (opens in a new tab) and Polymarket US (opens in a new tab) are separate US exchanges with different products and fee rules. Both are Available, dispute pending (as of October 13, 2026) in New York. Compare written contract definitions, current fees and account eligibility before funding; a larger offer does not establish a better platform.

How do Kalshi and Polymarket US compare?

Document-based comparison, checked October 13, 2026

Question	Kalshi	Polymarket US
U.S. exchange	KalshiEX LLC, listed in the CFTC DCM register.	QCX LLC d/b/a Polymarket US, separately listed in the CFTC DCM register.
What to read first	The exact contract’s rules and the order’s fee display; Kalshi says fees vary by market.	Polymarket US rules and order preview. Do not apply international Polymarket wallet, fee, or market guides to this product.
New York dispute	State lawsuit announced July 31, 2026.	State lawsuit announced September 24, 2026.
Current offer headline	“Trade $25 and Get $25!” for new users, subject to full terms.	“Deposit $10 get a $25 Trading Bonus!” A trading bonus is not asserted to be withdrawable cash.
What we cannot verify from these documents	Current account eligibility, final campaign conditions and an individual order’s total cost.	Current account eligibility, account-specific funding and withdrawal terms and final campaign conditions.

DCM designation identifies a federal exchange category. It does not decide the New York litigation or guarantee access to a particular contract.

How should you choose without relying on a bonus?

1. Confirm your location, age, account and product eligibility directly. New York’s complaints specifically dispute the platforms’ treatment of state gambling rules, including the 21-year minimum for mobile sports wagering.
2. Compare an actual contract you understand: event definition, close time, settlement source, cancellation treatment and available size. A shared topic does not mean identical settlement rules.
3. Compare executable prices and all applicable fees on the order preview. Kalshi’s fee guidance warns that some markets differ; this page does not assert a comparable universal Polymarket US rate.
4. Check funding, withdrawal holds, customer support and the complete promotion terms before placing money at risk. A reward should never make a losing position attractive.

What should a New York reader check before choosing?

Research both products if the contract and account access matter to you; do not treat either as “best in New York” on the evidence here. Kalshi has clearer publicly linked fee guidance in our source set. Polymarket US requires extra care to avoid mixing U.S. and international documentation. The recent state actions make a current eligibility check essential for both. If the conditions are unclear, you can follow the markets without registering or depositing.

What fees apply in the US?

Polymarket US charges orders that fill straight away (taker orders) 0.0695 × contracts × price × (1 − price), highest near 50 cents: about $1.74 per 100 contracts at 50¢. Orders that rest on the book pay no fee. Since 1:00 PM ET on October 19, 2026, Polymarket US has paid no flat rebate on resting orders for most traders; taker fees did not change. Kalshi charges 0.07 × contracts × price × (1 − price) on each executed trade, rounded up to the next cent (about $1.75 per 100 contracts at 50¢); some markets have their own rates. Use the order preview for the exact charge.

Sources

• CFTC designated contract market register (opens in a new tab) — checked October 14, 2026
• New York AG: Kalshi lawsuit, July 31, 2026 (opens in a new tab) — checked October 14, 2026
• New York AG: Polymarket lawsuit, September 24, 2026 (opens in a new tab) — checked October 14, 2026
• Kalshi fee guidance and official schedule — checked October 14, 2026
• Polymarket US market integrity and rulebook — checked September 29, 2026
• Polymarket international: U.S. trading notice — checked September 29, 2026

Frequently asked questions

Is Kalshi or Polymarket US legal in New York?

Kalshi and Polymarket US are Available, dispute pending (as of October 13, 2026) in New York. The state sued Kalshi on July 31, 2026 and Polymarket US on September 24, 2026; no court order blocks them. Check account, contract and location eligibility before funding.

Is Polymarket US the same as Polymarket.com?

No. The U.S. exchange is QCX LLC d/b/a Polymarket US. International help pages and screenshots do not establish U.S. terms or available markets.

Which has the better sign-up bonus?

The offer headlines describe different actions and reward types. Without complete campaign conditions, qualification and withdrawal rules, their dollar amounts are not a reliable like-for-like value comparison.

What is a prediction market contract?

It is a contract tied to a defined event. Read its resolution criteria, deadline, settlement source and exception rules.