How do betting exchanges work?
At a sportsbook, the book sets the price and takes the other side of your bet. On an exchange, other bettors set the prices. One user posts an offer, for example the Broncos at +130 for up to a certain amount, and another user takes it. The exchange holds both stakes, settles the result and charges its fee. It does not care who wins.
Some exchanges use the words back and lay. To back is to bet that something happens. To lay is to bet that it does not, which puts you in the bookmaker's seat for that bet. Offers sit in an order book, sorted by price, and a large bet can be filled in pieces by several smaller offers, which is called a partial fill. Whatever is left unmatched stays open until someone takes it or you cancel it.
Novig and ProphetX are the two exchanges our tools track. Their prices are open offers from other bettors, not sportsbook lines, so they can move in small steps and sit between the prices the books post. Availability and product type vary by state, so check where an exchange operates before you sign up.
Peer-to-peer betting
Exchanges are the main form of peer-to-peer betting, often shortened to P2P sports betting: you bet against another person, and the platform only matches the two sides. That changes three things. First, prices come from competition between bettors, so on popular games someone is usually willing to post close to the fair number. Second, you can be the one posting the price: offer the Broncos at +135 and wait for someone to take it, which works like a limit order on a stock exchange. Third, a winning bettor is just more volume for the exchange, so it has no reason to limit you for winning.
Peer-to-peer also has costs. If nobody wants the other side of your offer, it sits unmatched. Thin markets, such as small-conference games or obscure props, may have no offers at all. And a sports betting exchange in the USA operates under its own state approvals, which is why the same exchange can be open in one state and closed in the next.
Exchange vs sportsbook
| Exchange | Sportsbook | |
|---|---|---|
| Who sets the price | Other bettors' open offers | The book's traders and models |
| How it earns | A fee, often on net winnings | The margin built into every price |
| Typical market | Often tighter on popular games | Wider, with the vig on both sides |
| How much you can bet | Whatever offers are posted right now | The book's own limits for your account |
| Winning bettors | Welcome, they add volume | Often limited |
Neither is better for every bet. Exchanges shine on popular markets with plenty of offers. Sportsbooks can be better on thin markets, props and promotions, where an exchange may have few or no offers posted.
Real exchange prices from October 13, 2026
On October 13, 2026, the Odds Screen snapshot at 7:37 PM ET showed this moneyline for Seattle Seahawks at Denver Broncos. Adding the two sides' implied probabilities shows how much each market charges:
| Where | Seahawks | Broncos | Both sides add to |
|---|---|---|---|
| Novig (exchange) | -133 | +130 | 100.56% |
| ProphetX (exchange) | -134 | +129 | 100.93% |
| FanDuel (sportsbook) | -146 | +124 | 103.99% |
The exchange markets cost about half a point to one point across both sides, before fees. The sportsbook market cost about 4 points. That gap is why exchange prices so often show up as the best price on our boards. The fee still has to be counted, which is the next section.
Fees: the displayed price is not the whole story
Exchanges make money on fees, and the fee changes what a price really pays. ProphetX takes 2 percent of net winnings. A $100 bet at +129 wins $129 before the fee and $126.42 after it, so the price you are really getting is about +126. Our tools price every exchange quote after that fee, so an edge, a stake or a best price is never flattered by a number you cannot collect.
Novig's documented fee on pregame straight bets is zero, so its pregame prices are used as shown. Its live fees are not mapped in our tools, so live Novig prices are never marked actionable. Before you bet any exchange, read its current fee page: fees change, and some apply only to certain markets.
Notice the difference in how the cost lands. A fee on net winnings is paid only when you win, so a losing bet costs exactly its stake. A sportsbook's margin is charged on every bet through the price itself, win or lose. Comparing the two fairly means turning the exchange price into its after-fee equivalent first, which is what our boards do automatically.
Posted limits and liquidity
On a sportsbook, your limit is set by the book. On an exchange, it is set by the offers in front of you. Our tools show a posted limit: the most the exchange says it will take on that leg right now. Stakes are cut to fit it. If no limit is shown, the feed posted none, which is not proof that a big bet would be filled.
Offers also disappear. Another bettor can take the same price a second before you do, or the person who posted it can pull it. Treat an exchange price like any other quote: confirm it in the app before you count on it.
How exchanges fit line shopping, arbitrage and hedging
Because exchange markets are tight, they are a natural first stop when line shopping. They are also common legs in arbitrage and middles, where one side sits at a sportsbook and the other on an exchange, and they are handy for hedging a ticket you already hold.
A tight exchange market is also a good reference for fair odds, since there is less margin to remove. Our boards still build their fair estimates from several reference books, with each step and its limits described on how we test our tools.
Your next step
Frequently asked questions
Are betting exchanges available everywhere in the USA?
No. Availability and product type depend on the exchange and your state. Check the exchange's own terms for where it operates before you sign up; our odds screen notes the same thing beside its prices.
How do betting exchanges make money?
Through fees rather than a margin on every price. ProphetX, for example, takes 2 percent of net winnings. Our tools subtract that fee before comparing an exchange price with any other.
Why are exchange odds often better than sportsbook odds?
The prices come from other bettors competing to post offers, and the exchange's fee is usually smaller than a sportsbook's margin. On October 13, 2026 an NFL moneyline on Novig added up to 100.56 percent across both sides versus 103.99 percent at FanDuel.
What is a posted limit on an exchange?
The most the exchange says it will take on that bet right now, based on the offers posted. Our tools cut stakes to fit it. No limit shown means none was posted, not that any size will be filled.
Your next step
- 1Learn itBetting Exchange (this page)
- 2Apply itHow to line shop for the best odds →
- 3Run itOdds Screen →
- 4Master itDay 2: How sportsbooks make money →
Related terms
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