Kalshi vs Polymarket
Kalshi and Polymarket compared on regulation, who can trade, fees, market types, and who decides the outcome. Includes the separate Polymarket US exchange.
By BetScan Research · Updated · 9 min read
Kalshi and Polymarket both turn a yes-or-no question into a contract priced like a probability. They are not substitutes until you know which Polymarket you mean, who settles the contract, and which fee schedule the market is on.
This comparison sits in Comparisons. The longer versions are What Is Kalshi and What Is Polymarket. Prices and resolution have their own pages: how prices work and how markets resolve. What Is Novig covers the sports-only exchange that is not in the table below.
The short table
| Kalshi | Polymarket US | polymarket.com | |
|---|---|---|---|
| What it is | CFTC-regulated exchange (KalshiEX) | CFTC-regulated US exchange under the Polymarket US rulebook | International, crypto-settled platform |
| Who settles | Kalshi, from the source in the contract | The exchange, from the sources named in the rules | UMA Optimistic Oracle for prediction markets; Chainlink TWAP for up-down markets |
| Standard payout | $1 if the event occurs, $0 if it does not | $1 / $0, or $0.50 or last fair price when the rules say so | $1 redeem for winners; a 50-50 vote redeems at $0.50 |
| Dispute path | Exchange determination. You can request settlement; you do not vote | Exchange determination. Clarifications explain the rules | Bonded proposal, 2-hour challenge, then a token vote if disputed twice |
| Typical taker fee | 0.07 × C × P × (1−P) on the general schedule | 0.0695 × C × P × (1−P) | Category coefficient from 0 to 0.07. Geopolitics is 0 |
| 100 contracts at 50¢, taker | $1.75 on the general schedule | $1.74 | Depends on category. Crypto at 0.07 is $1.75 |
| Maker | $0 on most series. Some series charge 0.0175 × C × P × (1−P) | No charge. Volume-tiered rebate (0 below $10M/mo, up to −0.0104 at $200M+) | Not charged. A share of taker fees is rebated by category |
| Account | Dollars. Identity check. 18+ | Dollars. Identity check on the regulated exchange | Crypto balances. Eligibility is the international platform's, not the US exchange's |
| Market types | Politics, macro, culture, sports, and others | Event contracts, including sports, politics, and economic releases | Wide event markets, plus short-term up-down price markets |
Regulation and who can trade
Kalshi's status is the simplest of the three columns. KalshiEX is a designated contract market. A 2026 CFTC filing describes the contracts as binary, cash-collateralized, and cleared by Kalshi Klear. Individuals must be 18 or older. The October 1, 2026 member agreement blocks event-contract trading from a published list of countries, including the United Kingdom, Canada, Australia, and France.
Polymarket US is the column that matches that model. The August 5, 2026 rulebook is an exchange rulebook: contract outcomes are $1.00 or $0.00, and an outcome that cannot be determined goes through the exchange's review process. Settlement is final under that rulebook. This is the Polymarket product built as a US-regulated exchange.
polymarket.com is the column that does not match. Resolution docs put prediction markets on the UMA oracle. Fees, accounts, and eligibility are documented separately from Polymarket US. A price on one is not a price on the other, even when the headline matches. If you are in the United States, confirm which product your account is actually on before you compare a fee or a rule.
Fees, in one example
All three use a version of price × (1 − price), so the fee peaks at 50¢ and shrinks for heavy favorites and long shots.
Buy 100 Yes contracts at 40¢, as a taker, on the general schedule:
- Kalshi:
0.07 × 100 × 0.40 × 0.60 = $1.68, rounded up under its rounding rule. - Polymarket US:
0.0695 × 100 × 0.40 × 0.60 = $1.67before the exchange's cent rounding. - International Polymarket, politics (coefficient 0.04):
0.04 × 100 × 0.40 × 0.60 = $0.96. - International Polymarket, geopolitics: $0.
The interesting difference is the maker side. On Kalshi, posting a resting order is free unless the series is on the maker-fee list. On Polymarket US, makers are not charged, and since the October 19, 2026 tier change, maker rebates require at least $10 million in prior-month maker volume (paying 0 below that threshold and −0.0035 to −0.0104 in higher tiers). On the international site, makers are not charged, and they receive a fraction of the taker fees collected in that category.
Perpetual futures on Kalshi, table tennis and combos on Polymarket US, and up-down markets on polymarket.com are outside this example. Open the fee PDF or the docs page for the market in front of you.
What the markets cover
Kalshi and both Polymarket products list politics, macro data, and sports. Novig does not. Novig is sports contracts only, on its own CFTC exchange, with pre-game straight trades currently fee-free. If the question is a game, you may be choosing among three order books. If the question is a CPI print or an election, Novig is not a candidate. See What Is Novig.
Coverage is not the same as the same bet. Useful mismatches:
- Source. One contract uses the Bureau of Labor Statistics. Another uses a named news outlet, or, on polymarket.com, whatever the proposer can defend to UMA.
- Clock. Determination can wait on an official release (Kalshi often cites a few hours, sometimes more than twelve). A UMA market can resolve about two hours after an undisputed proposal, or several days if it is disputed twice.
- Sports details. Polymarket US includes overtime by default on most game contracts and excludes extra time for league soccer. Kalshi puts the equivalent choice in each contract's rules. Read both.
- Special settlement. Cancelled events, revisions, and "unknowable" outcomes can pay $0.50 or a last fair price. The title will not say so.
Who decides a dispute
This is the row that should decide which contract you research, not the logo.
On Kalshi, the exchange applies the written source. Participants can request settlement. They do not vote. The risk is rule ambiguity and waiting on a late source, not a token vote.
On Polymarket US, the exchange applies the written sources, and may post a clarification. Settlements are final under the rulebook. The risk profile is the Kalshi one: read the source ladder, especially the sports backup sources.
On polymarket.com, a proposer bonds typically $750, anyone can dispute for two hours, and a second dispute goes to UMA token holders for a vote Polymarket says takes about 48 hours. The risk is a proposal you think is wrong or early, and a vote you are not in. Winning that dispute is a trading skill the US exchanges do not ask of you.
How to choose
Pick the contract whose rules you can restate, on the exchange you are allowed to use, with a fee you have subtracted from the edge.
- If you want an exchange to apply a named source, compare the Kalshi contract and the Polymarket US contract on the wording, not on the topic.
- If you are looking at a polymarket.com URL, budget for the oracle process and the category fee. Do not describe that price as "the regulated Polymarket price."
- If the book is thin on both, the cheaper fee does not matter. You cannot trade the midpoint. How prices work covers the spread.
- Then run the checklist in How to Research a Prediction Market Before You Trade. BetScan does the source-gathering step for the link you paste and shows the range next to the market price.
Sources
- Kalshi fees, effective July 7, 2026: Fee schedule PDF
- Kalshi eligibility and restrictions: Signing up, Member agreement
- Kalshi settlement: Market outcomes
- Polymarket US fees: docs.polymarket.us/fees
- Polymarket US rules and settlement: Rulebook PDF, Market resolution, Sports FAQs
- International Polymarket: Resolution, Fees
Frequently asked questions
Which is more regulated, Kalshi or Polymarket?
Kalshi and Polymarket US are both CFTC-regulated designated contract markets with published rulebooks and exchange-determined settlements. The international site at polymarket.com is a separate platform. Its prediction markets resolve through the UMA oracle, not through that US exchange.
Which is cheaper?
On a standard taker trade, the formulas are close. Kalshi's general schedule effective July 7, 2026 is 0.07 × contracts × price × (1 − price). Polymarket US is 0.0695 on the same shape. One hundred contracts at 50 cents cost $1.75 on Kalshi's general schedule and $1.74 on Polymarket US. International Polymarket fees depend on the category and are zero for geopolitics. Your market may not be on the general schedule.
Do they list the same markets?
Often the same topic, not the same contract. A Fed, election, or game market can differ in the source, the deadline, whether overtime counts, and who settles disputes. Compare the rules, not the titles.
Where does Novig fit?
Novig is a third CFTC-regulated exchange, approved June 16, 2026, and it lists sports only. See What Is Novig. It is not a column in the political or macro comparison.
Research a market in minutes
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BetScan articles are research and education, not financial advice. BetScan does not place trades, hold funds or operate a market.