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Betting Insider

Guide

Free bet calculator: what your free bet is worth

A free bet is never worth its face value, because the bookmaker keeps the stake. Our free bet calculator shows how much it pays if it wins, how much the same stake would have paid in cash and what the free bet is worth on average at the odds you choose, so you can decide where to use it.

By Callum Reid, bookmaker reviews & racing · fact-checked by Priya Nair · reviewed 21 October 2026

  • First 13 days of odds
  • Matchbook2.14%PL 1.96 · L2 2.50
  • Smarkets3.05%PL 2.42 · L2 2.92
  • Betfair4.38%PL 4.02 · L2 4.87
  • Betfair Sportsbook5.90%PL 5.09 · L2 5.75
  • Coral5.92%PL 5.63 · L2 5.87
  • Unibet6.33%PL 4.59 · L2 6.58
  • Ladbrokes6.59%PL 6.54 · L2 6.55
  • Paddy Power7.10%PL 6.83 · L2 7.02
  • Betano7.27%PL 7.51 · L2 6.55
  • BetVictor7.27%PL 7.51 · L2 6.54
  • Casumo7.31%PL 5.07 · L2 10.55
  • Sky Bet7.35%PL 6.97 · L2 7.41
  • LeoVegas7.54%PL 7.72 · L2 7.88
  • Betway7.71%PL 7.12 · L2 7.42
  • Virgin Bet7.99%PL 7.36 · L2 7.11
  • William Hill8.87%PL 7.16 · L2 9.04
  • Betfred8.88%PL 5.54 · L2 8.47
  • Grosvenor Sport9.15%PL 6.73 · L2 11.24
  • 888sport9.28%PL 7.96 · L2 9.56
  • LiveScore Bet9.54%PL 6.75 · L2 11.73
  • BoyleSports10.81%PL 6.28 · L2 10.73

Work out what your free bet is worth

Enter the free bet and the odds you have in mind. The calculator shows what you collect if the bet wins, what the same stake would have paid in cash, the average value of the free bet at fair odds and how often a bet at that price would win. Switch to “stake returned” if your terms say so.

Free bet calculator

What your free bet is really worth

Fractional (5/2), decimal (3.50) or "evens"

If it wins you get
£20
The same stake in cash would pay
£30
Average value at fair odds
£6.67 (67% of face value)
Chance the bet wins at fair odds
33%
A £10 free bet that wins, at five prices
  • 1/21.50 £533% of face value on average
  • evens2.00 £1050% of face value on average
  • 2/13.00 £2067% of face value on average
  • 4/15.00 £4080% of face value on average
  • 9/110.00 £9090% of face value on average

Paid to youStake kept by the bookmaker

Fair odds leave out the bookmaker's margin, which trims every figure a little further. The average is over many bets; a single free bet either wins or pays nothing.

Why a free bet is worth less than it says

The difference comes from one line in the terms: the stake is not returned. A £10 cash bet at 2/1 that wins pays back £30, your £10 plus £20 profit. A £10 free bet at the same price pays £20, the profit only. The £10 you never see is the main cost of a free bet, and it is why the face value overstates what you are getting.

That missing stake weighs most at short prices. Back a 1/2 favourite with a £10 free bet and a win pays £5, a third of the face value on average. At evens the average rises to half, and at 4/1 to four fifths. The chart above shows the same pattern at five common prices, with the stake the bookmaker keeps marked on each bar.

How to choose the odds for a free bet

There is no single right price, only a choice between a likely small return and an unlikely bigger one. A short price wins more often and pays little. A long price wins rarely but keeps more of the value when it does. Decide which suits you before you look at the market, not after the credit is about to expire.

Check the terms before you place it. Many free bets carry their own minimum odds, and some can only go on bet builders, accumulators or particular markets. Our free bets page lists every current welcome offer with its minimum price and where the credit can be used, and lets you filter them.

Remember the margin too. The calculator’s average assumes fair odds, the price a market would show with no bookmaker’s edge built in. Real prices are a little shorter, so a free bet’s true average is slightly lower again. Our betting margin calculator shows how much a market’s prices are trimmed.

Stake returned or stake not returned

Almost every UK welcome offer pays its credit as stake-not-returned free bets, often shortened to SNR in the terms. A few promotions return the stake as well, and a money back offer that refunds in cash gives you money you can stake normally. Those are worth more than the same amount in SNR credit, which the calculator shows when you switch the setting.

A free bet is a stake you never paid for, not a way to make money. It wins or loses like any other bet, and the welcome offer exists to get you betting. Set your limits before you claim one, and use the deposit limits and time-outs every licensed bookmaker offers. Our safer gambling page lists free support.

FAQ

Frequently asked questions

How do you calculate free bet winnings?

For the usual stake-not-returned free bet, multiply the free bet by the decimal odds and take away the stake. A £10 free bet at 3.00 pays £30 minus £10, so £20. If the terms say the stake is returned, you receive the full £30, which is rare at UK bookmakers.

What odds should I use a free bet on?

Longer odds keep more of a free bet's average value, because the missing stake matters less the bigger the price. At evens a free bet is worth about half its face value; at 4/1 about four fifths. The trade-off is that a longer price wins less often, so many free bets pay nothing.

What does stake not returned mean?

It means the free bet amount itself is not paid back when the bet wins. You receive the profit only. Almost every UK welcome offer pays its credit this way, and the full terms say so, often shortened to SNR. A stake-returned free bet pays the stake back as well.

Is this a matched betting calculator?

No. It values a free bet as a normal bet that either wins or loses. Matched betting places an opposite lay bet on an exchange to lock in a share of the value whatever happens. Bookmakers may restrict accounts that do this, which our account restrictions guide explains.

Can a free bet be worth more than its face value?

Not on average. A stake-not-returned free bet is always worth less than its face value, and only a stake-returned free bet at fair odds reaches the full amount. The bookmaker's margin trims either figure a little further, so the calculator's average is an upper limit.