Betting exchanges explained
How exchanges differ from bookmakers, what backing and laying mean, and how commission changes the real price.
A bookmaker sets prices and takes the other side of your bet. An exchange is a marketplace where customers bet against each other, and the exchange earns commission on winnings. Betfair Exchange, Smarkets and Matchbook are the UK's main exchanges.
Backing and laying
To back an outcome is to bet on it happening, as with a bookmaker. To lay is to bet against it, taking the bookmaker's role. If you lay £10 at 3.00 and the outcome wins, you pay out £20. That £20 is your liability, and it must be in your account when you place the bet.
Commission changes the real price
Exchanges take a percentage of net winnings on a market. On a £10 back bet at 3.00 you win £20 before commission:
| Commission | Paid out | Effective price |
|---|---|---|
| 2% | £19.60 profit | 2.96 |
| 5% | £19.00 profit | 2.90 |
The effective price formula is 1 + (price − 1) × (1 − commission). Our tables use this formula, so an exchange price is only marked as the best price if it still beats the bookmakers after commission. The listed price is what you see on the exchange.
Liquidity
An exchange price is only available for the amount other customers have offered. Popular matches near kick-off often have plenty of money available, while lower leagues and early markets can be thin. The price you see may not cover your full stake, and unmatched bets simply wait until someone takes them or you cancel.
When an exchange makes sense
Exchanges are worth checking when you want to bet against an outcome, when you bet larger stakes, or when a bookmaker has limited your account. For small stakes on popular markets, a bookmaker's best price can still be better once you count commission.
Guides are for information only and are not betting advice. Only bet what you can afford to lose. See our responsible gambling page for support.
