Prediction markets vs sports betting

On a phone screen, a sports contract on Kalshi and a moneyline at a sportsbook can look almost identical. Underneath, they are built differently, priced differently and regulated by different governments. Those differences affect what you pay, who can take part and how stable access is.

At a glance

Exchange vs house

A sportsbook is your counterparty. It sets the odds, takes your bet and profits when its prices are right over many bets. A prediction market is an exchange: it matches your order with another user’s and earns a fee whichever side wins.

That changes the incentives. An exchange benefits from volume, not from your losses. It also means prices move with supply and demand rather than at a trader’s discretion, and you can post your own price with a limit order instead of accepting the one offered.

Pricing: vig vs fees, worked through

Standard illustration, not a quote from any sportsbook: a game is priced at -110 on both sides. You risk $110 to win $100.

• Break-even win rate: 110 ÷ 210 = 52.38%.
• If the book takes equal money on both sides, it collects $220 and pays $210 to winners, a hold of $10 ÷ $220 = 4.55%.

Now the prediction-market equivalent: Yes on the same team at 50¢.

On fees alone, the exchange route is cheaper. The spread changes that. If the best Yes ask is 51¢ rather than 50¢, a Kalshi taker pays 51¢ plus a 1.75¢ fee (0.07 × 0.51 × 0.49, rounded up at the 100-contract level to $1.75), so the break-even rises to about 52.75%, worse than the -110 illustration. Novig’s zero pre-game fee likewise only helps if its spread is tight.

The practical lesson: compare the all-in price you would actually pay, not the headline fee. Our fee guide shows how costs change across prices.

Age: 18 vs 21

Kalshi, Robinhood, FanDuel Predicts and DraftKings Predictions set 18 as the minimum age for prediction markets. Most state sports-betting laws set 21.

This gap is one of the most contested points between platforms and states. Ohio’s Casino Control Commission cited under-21 users among its reasons for a $5 million fine notice to Kalshi in April 2026, and Fortune reported on the scale of under-21 trading in August 2026.

Regulation: federal vs state

Prediction markets operate under the Commodity Exchange Act, overseen by the CFTC. Sportsbooks are licensed and taxed state by state.

The legal fight is over which framework applies to sports contracts. The 3rd Circuit (April 6, 2026) found they are likely swaps under exclusive federal jurisdiction. The 9th Circuit (August 28, 2026) and 6th Circuit (September 25, 2026) disagreed, holding that state gambling law can apply. Louisiana’s Gaming Control Board has formally advised that sports prediction markets amount to illegal sports wagering. The Supreme Court has been asked to resolve the split. For the reasoning behind the two most recent losses, see our reports on the 9th Circuit’s Nevada ruling and the 6th Circuit’s Ohio and Tennessee ruling; our legal tracker follows each state.

States are also starting to tax the platforms rather than ban them. North Carolina enacted a 6% tax on net trading-fee revenue from January 1, 2027, and Kentucky a 14.25% excise tax on transaction fees from the same date.

Availability

Sportsbooks are only available in states that have legalized and licensed online sports betting. Prediction markets reach further. FanDuel Predicts’ official offer terms list 18 states for sports contracts, including California and Texas. DraftKings Predictions reportedly offers sports only in states where DraftKings has no sportsbook licence.

But prediction-market access is less stable. Court rulings and orders have taken Kalshi’s sports contracts out of Massachusetts, Michigan, Nevada, Utah and Washington, and availability can change within days of a ruling.

Limits

A sportsbook sets its own maximum stakes because it carries the risk of every bet. On an exchange, the platform is not exposed to the outcome, so the practical limit is how much liquidity sits in the order book at your price, plus funding limits. Polymarket US, for example, allows debit and ACH deposits of up to $50,000 a day. Large orders in thin markets will move the price against you.

Taxes

Treat this section as a flag, not guidance. How prediction-market profits should be classified is unsettled, and the IRS has issued no specific guidance on event contracts, according to secondary reporting. Keep a record of every trade, including fees, and speak to a tax professional. This is not tax advice.

Consumer protections

Prediction-market exchanges must meet CFTC core principles, and the CFTC polices trading on them. Its enforcement division issued an advisory on the misuse of nonpublic information in February 2026, and it has since penalized individual traders for manipulation and insider trading. Sportsbooks answer to state gaming regulators, which set rules on advertising, age checks and responsible gambling tools in their states. State attorneys general argue that prediction markets bypass those protections; the platforms argue federal oversight is enough. Both views are being tested in court.

Which should you choose?

A prediction market may suit you if you want to set your own prices with limit orders, trade out before the result, pay a disclosed fee rather than a built-in margin, or you live in a state without a legal sportsbook where contracts are available.

A sportsbook may suit you if you prefer a fixed price from a single counterparty, value the stability of a state licence, or are in a state where prediction-market sports contracts are blocked.

Either way, set a budget first and see our responsible play resources.