What is Kalshi? How it works, fees, payouts and tennis markets

Kalshi is a US exchange where you buy and sell yes-or-no contracts on real events, including tennis matches. Each contract trades between 1¢ and 99¢ and pays $1 if you're right, so the price works as the market's estimate of the chance: 70¢ means about 70%. The US Commodity Futures Trading Commission (CFTC) designated Kalshi's exchange, KalshiEX LLC, as a contract market in November 2020. Everything on this page comes from Kalshi's and the CFTC's own pages, checked on 1 November 2026.

I run 77 Tennis, a free demo that uses live prediction market prices, so I read these markets every day. I'm not affiliated with Kalshi, and nothing here is a recommendation to use it. If the idea of a prediction market is new, start with what are prediction markets.

What Kalshi is

Kalshi's help center calls it the first regulated exchange where you can buy and sell contracts on the outcome of events. The questions range from interest rates and economic data to awards, court cases and sports. Every contract is a yes-or-no question with a fixed payout: a Yes contract pays $1 if the answer turns out to be yes and nothing if it doesn't.

Kalshi says it makes money by charging a transaction fee, and that it has no financial stake in which way an event goes. The other side of your trade is another member. Kalshi's page on prices says it matches someone buying Yes with someone buying No, and that the two stakes together must equal $1. That's the main difference from a bookmaker, which sets its own odds and takes the other side itself, as tennis trading vs tennis betting explains.

How Kalshi works: prices, buying and selling

• The price is a probability. Kalshi's help page gives the example of a Yes price of 70¢, which corresponds to a 70% chance. The No price moves the opposite way.
• You can sell before the end. A quick order sale sells your contracts at the current market price, and Kalshi shows the average price and estimated payout before you confirm.
• Or you can hold to settlement. When the outcome is known, winning contracts pay $1 and losing ones pay nothing. Each market has a Timeline and Payout section showing when it closes and when it's expected to pay, and Kalshi advises reading it before you trade.

To turn a Kalshi price into decimal or American odds, use the odds converter. The idea underneath is the same one explained in how tennis prices work: a contract that pays $1 is worth roughly its chance of paying.

What Kalshi charges

Kalshi's fee schedule page, checked on 1 November 2026, lists these fees per 100 contracts. A taker order fills straight away against an order already on the book. A maker order rests on the book until someone accepts it.

The fee depends on the contract's price, which is why the schedule shows a range rather than one number. Kalshi's fees page says a maker fee is charged only when a resting order is actually filled, that cancelling a resting order costs nothing, and that you can see the exact fee before you confirm by clicking the "i" icon next to "You're buying". The schedule page also said no fee changes were scheduled.

If you compare a Kalshi price with a bookmaker's odds, take the bookmaker's margin out first with the no-vig calculator. Otherwise you're comparing a price with a margin built in against one without.

How to cash out, and how long payouts take

Cashing out on Kalshi has two steps. First, turn your position into cash, either by selling it at the current price or by waiting for the market to settle. Second, withdraw the cash. Kalshi's help pages list the two main withdrawal methods like this:

Debit card withdrawals have a daily limit that Kalshi says is personal to your account and rises with account activity. Kalshi also has help pages for crypto, PayPal and Venmo withdrawals, each with its own terms.

Kalshi's tennis markets

Kalshi runs an ATP tennis match series and WTA match markets too. I read the rules of a live ATP match market through Kalshi's public market data on 1 November 2026. They said:

• The market resolves Yes if your player wins the match after a ball has been played.
• If the match doesn't start because of an injury, a walkover, a forfeit or any other cancellation, the market resolves to a fair price in accordance with Kalshi's rules.
• If the match is postponed or delayed, the market stays open and closes after the rescheduled match finishes, within two weeks.
• The series lists the ATP as its settlement source.

The walkover rule is the one to remember, because Polymarket pays 50¢ a share instead. It's also why a price gap between the two is rarely risk-free, as arbitrage betting explained shows. Kalshi vs Polymarket for tennis puts the two side by side, and what happens if a player retires covers the cases that start but don't finish.

Is Kalshi legit?

Here's what the official record says. On 4 November 2020 the CFTC announced that it had designated KalshiEX LLC as a contract market under the Commodity Exchange Act, after finding that it could comply with the rules for designated contract markets. Kalshi's help page says it is regulated by the CFTC, which it describes as an independent US government agency that has regulated US derivatives markets since 1974. Kalshi's site also states that members risk losing their cost to enter any transaction, including fees.

Regulation is about how the exchange is run. It doesn't make a trade safe, and it doesn't protect you from a loss.

Is Kalshi gambling?

Kalshi and the CFTC call what Kalshi lists event contracts. In a notice published in March 2026, the CFTC said it has used that term since at least 2008 for derivative contracts typically with a binary payoff based on the outcome of an event, and it defined a prediction market as a CFTC-registered exchange that offers them. In the same month the CFTC's chairman said the agency will exercise its exclusive jurisdiction over prediction markets. How the law where you live treats Kalshi is a question for Kalshi's Member Agreement and your local rules. This page doesn't answer it.

Signing up, the demo, combos and taxes

• Who can sign up. Kalshi's sign-up page asks for age 18 or over and identity verification. It says Kalshi is now accessible internationally but that some jurisdictions remain restricted, as listed in the Kalshi Member Agreement.
• The demo. Kalshi runs a separate demo site, demo.kalshi.co, with mock funds. Its help page says no real money is involved and nothing you do there affects your real account.
• Combos. A combo puts several outcomes into one position. Kalshi says it pays at most $1 a contract, pays nothing if any leg settles at $0, and can't be cancelled once it's filled.
• Taxes. Kalshi says it issues 1099 forms to members who meet IRS reporting thresholds, and that it can't give members tax advice.

If you want to try tennis markets without money first, the 77 Tennis demo uses live prediction market prices with $1,000 of play money.

Sources

All checked on 1 November 2026: the CFTC's press release 8302-20 of 4 November 2020; the CFTC's Federal Register notice Prediction Markets of 16 March 2026 and press release 9194-26; Kalshi's fee schedule; and these Kalshi help center articles: How is Kalshi regulated, How does Kalshi make money, How are prices determined, Quick Order Sale, Timeline and Payout, Fees, Bank Withdrawals, Debit Card Withdrawals, Signing Up as an Individual, Creating and Using a Demo Account, Combos, and What Tax Documentation Does Kalshi Provide. The tennis rules come from an open ATP match market in Kalshi's public market data. Where this page and those pages disagree, those pages win.

FAQ

What is Kalshi?

A US exchange where you trade yes-or-no contracts on events, priced between 1 and 99 cents and paying $1 if you're right. The CFTC designated its exchange, KalshiEX LLC, as a contract market in November 2020.

Is Kalshi legit?

The CFTC designated KalshiEX LLC as a contract market on 4 November 2020, and Kalshi says it is regulated by the CFTC. That's about how the exchange is run. It doesn't make any trade safe, and Kalshi itself says members risk losing what they put in, including fees.

How long does Kalshi take to pay out?

Winning contracts pay $1 when the market settles, and each market's Timeline and Payout section shows when that's expected. Kalshi's help pages say debit card withdrawals typically arrive within a few hours and bank transfers within a few business days.

Does Kalshi have tennis markets?

Yes. It lists ATP and WTA match markets. The ATP markets settle on the official ATP result once a ball has been played, and resolve to a fair price if the match never starts.

Can I try Kalshi without real money?

Kalshi has a separate demo site with mock funds. For tennis, the 77 Tennis demo uses live prediction market prices with $1,000 of play money.