A €10 free bet is not worth €10
Most free bets are "stake not returned": if the bet wins, you get the net winnings but not the stake. A €10 free bet played at 2.00 pays €10 if it wins and nothing if it loses. Its average value therefore depends on the odds you choose and on the true chance of the bet.
On a bet at fair odds (no margin), the average value of a free bet is:
Value ≈ amount × (1 − 1 / odds)
- Odds: 1.50 — Share of the free bet kept on average: 33%
- Odds: 2.00 — Share of the free bet kept on average: 50%
- Odds: 3.00 — Share of the free bet kept on average: 67%
- Odds: 5.00 — Share of the free bet kept on average: 80%
The higher the odds, the more the free bet is worth on average, because the lost stake (which was never yours) matters less. The flip side: results vary more; at 5.00, you win one time in five.
The margin cuts everything
At a real bookmaker, odds include a margin. The real value is therefore: true chance × (odds − 1) × amount. A €10 free bet at odds of 3.00 with a 31% true chance is worth 0.31 × 2.00 × 10 = €6.20, not €6.67. The best use of a free bet is high odds and close to the fair price, ideally a bet where the bookmaker pays more than the true chance.
The free bet converter does exactly this calculation: choose your bookmaker, the type of offer and the required odds range, and it finds, among matches in the next four days, the price that gets the most out of it, based on the true chance of each outcome.
Locking in the value of a free bet
If you prefer a result known in advance to an average gain, you can hedge the free bet: back the opposite outcome elsewhere, at another bookmaker or by laying it on a betting exchange (see the guide on betting exchanges). Done right, the hedge usually locks in 65 to 80% of the free bet amount whatever the result, depending on the odds and commission.
With a lay, the stake is worked out as follows: lay stake = free bet × (free bet odds − 1) / (lay odds − commission). Example: a €10 free bet at 5.00, laid at 5.20 with 5% commission: lay stake = 40 / 5.15 = €7.77. If the bet wins: €40 − 7.77 × 4.20 = €7.37; if it loses: 7.77 × 0.95 = €7.38. About €7.40 either way, or 74% of the free bet.
Refund-if-it-loses offers
Another common offer: you stake your own money; if the bet loses, the bookmaker refunds you with a free bet. Here, the value depends on the chance of losing and on what the free bet will be worth afterwards. The converter handles this case too.
The terms to read
- Minimum odds required (often between 1.30 and 2.00).
- Expiry date of the free bet.
- Wagering requirements: some bonuses must be played through several times before any withdrawal.
- Excluded markets: sometimes in-play, parlays or certain sports.
Key takeaways
A free bet is worth less than its face value, and its value depends on the odds: higher is usually better, as long as the price stays close to fair. Do the maths before you bet, or hedge for a certain gain. And remember that bonuses are a marketing tool: they change nothing about the margin on the bets that follow.