Betting calculator
Lay Liability Calculator
Use this calculator to work out the liability on a lay bet, including possible profit after exchange commission.
Enter your lay bet
Add the lay stake, lay odds and exchange commission to calculate your liability and possible result.
Laying £100.00 at odds of 3.00 creates a liability of £200.00. If the selection loses, the profit after 2% commission is £98.00.
What is lay liability?
Lay liability is the amount you risk when placing a lay bet on a betting exchange. It is the amount you would need to pay out if the selection you laid goes on to win.
This is different from a normal back bet. With a back bet, your stake is usually the amount at risk. With a lay bet, your liability can be larger than the lay stake depending on the odds.
Lay liability formula
Lay liability = lay stake × (lay odds − 1)
For example, if you lay £100 at odds of 3.00, the liability is:
£100 × (3.00 − 1) = £200
What happens when a lay bet wins?
A lay bet wins if the selection does not win. For example, if you lay a horse and the horse loses, your lay bet wins.
When a lay bet wins, you win the backer’s stake. On a betting exchange, commission is usually taken from your net winnings.
Lay profit after commission = lay stake × (1 − commission)
So if you lay £100 and the commission is 2%, your profit if the selection loses is £98.
What happens when a lay bet loses?
A lay bet loses if the selection wins. In that case, you pay the liability.
For example, if you lay £100 at odds of 3.00, your liability is £200. If the selection wins, your loss is £200.
| Lay stake | Lay odds | Liability | If selection loses | If selection wins |
|---|---|---|---|---|
| £100 | 3.00 | £200 | £98 profit after 2% commission | £200 loss |
Lay stake vs lay liability
Lay stake and lay liability are often confused.
| Term | Meaning |
|---|---|
| Lay stake | The amount the backer is trying to win from you. |
| Lay liability | The amount you risk if the selection wins. |
| Exchange commission | A fee charged on winning exchange bets. |
At short odds, the liability may be close to the lay stake. At bigger odds, the liability can become much larger.
Why lay liability matters
Lay liability matters because it shows your real exposure. A lay stake of £100 can look simple, but if the lay odds are 10.00, the liability is £900.
| Lay stake | Lay odds | Liability |
|---|---|---|
| £100 | 2.00 | £100 |
| £100 | 3.00 | £200 |
| £100 | 5.00 | £400 |
| £100 | 10.00 | £900 |
Lay liability and hedging
Lay liability is especially important when hedging. If you back a selection first and then lay it later, the lay stake and lay liability determine your final profit or loss across both outcomes.
If you want to calculate a full back-and-lay hedge, use the Hedge Bet Calculator. It includes back first, lay later and lay first, back later modes.
Common lay betting mistakes
Looking only at the lay stake
The lay stake is not the full amount at risk. The liability is the amount you can lose if the selection wins.
Forgetting commission
Exchange commission reduces your profit when the lay bet wins. It usually does not reduce your liability when the lay bet loses.
Laying at high odds without checking exposure
High lay odds can create large liabilities. This can be risky if the stake is too large relative to your bankroll.
Confusing back bets and lay bets
Backing means betting that something will happen. Laying means betting against it. The risk and payout structure are different.
Related betting calculators
Lay liability calculator FAQs
What does a lay liability calculator do?
A lay liability calculator works out how much you risk when placing a lay bet at a given stake and odds.
How do you calculate lay liability?
Lay liability is calculated as lay stake multiplied by lay odds minus one. For example, £100 at odds of 3.00 gives liability of £200.
Do I pay commission on a losing lay bet?
Commission is usually charged on net winnings, not on losing bets. If your lay bet loses, your loss is normally the liability.
Is lay stake the same as liability?
No. The lay stake is the amount you can win before commission if the selection loses. The liability is the amount you risk if the selection wins.
Why is lay liability higher at bigger odds?
Because you are offering a larger payout to the backer if the selection wins. The liability grows as the odds increase.