Free Bet or Deposit Bonus: Which Is Actually Worth More?
A £10 free bet and a £10 deposit bonus look like the same promotion written two ways. They are not the same product, they are not worth the same money, and one of them can be worth less than nothing while still being described as a £10 bonus. Each has exactly one formula behind it, both formulas are short, and once you have them the comparison stops being a matter of opinion. This guide sets out both, gives the wagering multiple above which a deposit bonus is guaranteed to lose money in expectation, and identifies the single price at which the answer flips from one product to the other.
A free bet is not the amount printed on it
Nearly every UK free bet is stake not returned. Place a £10 free bet at decimal odds of 3.00 and a winning bet pays £20, not £30: the token is consumed, and only the profit reaches your balance. So the fraction of face value you can convert into withdrawable cash is not 100% but (o − 1) / o, where o is the decimal price.
That fraction rises with the odds, which is why a free bet placed on a short-priced favourite throws away most of its value. It never reaches 100%, because it cannot: the stake is always gone. And it is slightly lower again in practice, because the price you are given already contains the bookmaker's margin. The table below shows both — the raw arithmetic, and the figure after allowing for a 5% margin, which is typical of a two-way market.
| Odds used | Retained (fair price) | Retained (5% margin) | Same as a bonus at |
|---|---|---|---|
| 1.50 | 33.3% | 31.7% | 17.1x |
| 2.00 | 50.0% | 47.5% | 13.1x |
| 2.50 | 60.0% | 57.0% | 10.7x |
| 3.00 | 66.7% | 63.3% | 9.2x |
| 4.00 | 75.0% | 71.2% | 7.2x |
| 5.00 | 80.0% | 76.0% | 6.0x |
| 10.00 | 90.0% | 85.5% | 3.6x |
The last column is the point of the table, and we return to it below. If you want to run your own numbers, including the rarer stake-returned variety, the free bet calculator does this arithmetic for any stake and price.
A deposit bonus has a line above which it is worth nothing
A deposit bonus is credited in full but locked behind a wagering requirement: a multiple of the bonus that you must stake before any of it can be withdrawn. The common misreading is that this is money you must lose. It is not — it is money you must turn over, and most of it comes back as winnings along the way. What it costs you is the house edge applied to that turnover.
Write it out and the whole product collapses into one line. A bonus B at a wagering multiple W requires turnover of W × B. On a game with return to player RTP, the expected cost of that turnover is (1 − RTP) × W × B. The bonus is worth keeping only while B exceeds that cost, so the break-even multiple is:
W* = 1 / (1 − RTP)
The wagering multiple at which a deposit bonus has an expected value of exactly zero. It depends only on the game, never on the size of the bonus — the bonus cancels out of both sides.
| Game RTP | House edge | Break-even wagering |
|---|---|---|
| 94% | 6.0% | 16.7x |
| 95% | 5.0% | 20.0x |
| 96% | 4.0% | 25.0x |
| 97% | 3.0% | 33.3x |
On the 96% slots that carry most UK bonus play, the line sits at 25x. That single number does more work than any comparison table of operators: a headline wagering requirement above 25x on a 96% game is negative in expectation before a single further term is applied, and the further terms only ever make it worse. Here is a £10 bonus at each level.
| Wagering | Turnover needed | Expected cost | Kept, as % of bonus |
|---|---|---|---|
| 10x | GBP 100 | GBP 4 | 60% |
| 20x | GBP 200 | GBP 8 | 20% |
| 25x | GBP 250 | GBP 10 | 0% |
| 35x | GBP 350 | GBP 14 | -40% |
| 50x | GBP 500 | GBP 20 | -100% |
The 35x row is the one worth sitting with, because 35x is a market standard rather than an outlier. It is not a smaller bonus than advertised; on average it is a cost. The wagering calculator computes the same figures for any deposit, match percentage and contribution rate, and casino bonus wagering explained covers the mechanics in full.
Putting them on the same scale
Both products now reduce to one number: the fraction of face value you expect to keep. For a free bet that is (o − 1) / o, adjusted for margin. For a deposit bonus it is 1 − (1 − RTP) × W. Setting them equal turns any free bet into its deposit-bonus equivalent, which is the last column of the first table: a free bet used at evens keeps about 47.5%, and so does a deposit bonus carrying 13.1x wagering on a 96% slot.
That comparison is unkind to the deposit bonus in the open market, where 30x to 40x is normal, but it is much closer under the UK wagering cap. At 10x a bonus keeps 60% of its face value, and a free bet keeps 60% when it is placed at decimal odds of about 2.71. That is the crossover:
Below odds of roughly 2.71, the capped bonus is worth more. Above it, the free bet is.
Computed at a 96% RTP and a 5% margin in the price. Raise the RTP or lower the margin and the crossing price falls; a lower RTP pushes it up. The comparison is between two expectations, not two certainties.
It follows that the standard advice to spend a free bet on a long shot is right about the direction and silent about the reason. The value of a free bet is created entirely by the stake you do not get back, so it rises with the price. The value of a deposit bonus is destroyed entirely by turnover, so it falls with the multiplier. They are governed by opposite variables, which is why no general answer to "which is better" exists without naming a price.
The three terms that move the answer after you have claimed
Everything above assumes the headline terms are the only terms. They rarely are, and each of the three below acts on the deposit bonus only, which widens the gap in the free bet's favour.
| Term | What it does to the sum |
|---|---|
| Game contribution | Divides the effective turnover by the contribution rate. A game at 20% multiplies the requirement fivefold, so a 10x bonus behaves like a 50x one. |
| Max bet while wagering | Caps the stake per round, turning the requirement into a number of spins and therefore into hours. It does not change the expected cost, only the time it takes to pay it. |
| Max withdrawal cap | Truncates the upside while leaving the downside intact, which lowers the expected value without appearing anywhere in the headline multiplier. |
Each is covered on its own page: game contribution, the max bet rule and the max withdrawal cap. A free bet has none of the three. Its terms are usually a minimum price and an expiry date, both of which you can see before you use it.
Common questions
Is a £10 free bet worth £10?
No. Almost every UK free bet is stake-not-returned, which means the stake is deducted from the return, so you keep only the profit. On a fair price at decimal odds o you retain (o − 1) / o of the face value: 50% at odds of 2.00, 66.7% at 3.00, 80% at 5.00. Allowing for a typical 5% margin in the price, a £10 free bet placed at evens is worth about £4.75 in expectation, not £10.
At what wagering requirement does a deposit bonus become worthless?
At a wagering multiple equal to 1 divided by the house edge. On a 96% RTP slot the house edge is 4%, so the break-even multiple is 25x: a bonus carrying exactly 25x wagering has an expected value of zero before any other term is applied. Above 25x the expected cost of the turnover exceeds the bonus itself. On a 94% RTP game the line falls to 16.7x, and on a 97% game it rises to 33.3x.
Is a 35x bonus a bad offer?
On a 96% RTP slot, yes, taken on its own arithmetic. Clearing 35x means staking 35 times the bonus, and 4% of that turnover is expected to be lost, which is 1.4 times the bonus. The expected value is therefore about minus 40% of the bonus. That does not mean every player loses that amount, because the distribution is wide, but it does mean the average outcome is a loss and the offer is not free money.
How do I compare a free bet and a deposit bonus of the same size?
Convert both to the fraction of face value you expect to keep. For a free bet that fraction is (o − 1) / o adjusted for the margin in the price. For a deposit bonus it is 1 minus the house edge times the wagering multiple. A free bet used at evens keeps about 47.5%, which is the same as a deposit bonus carrying roughly 13x wagering on a 96% slot. Very few deposit bonuses are that low.
Under the UK 10x wagering cap, which is better?
At 10x on a 96% RTP game a deposit bonus retains about 60% of its face value. A free bet retains 60% when it is placed at decimal odds of about 2.71 after allowing for margin. So below roughly 2.71 the capped deposit bonus is worth more, and above it the free bet is worth more. The crossover is a price, not a preference, and it moves with the RTP of the game you intend to play.
Sources and method
Every figure on this page was recalculated from the two formulas before publication rather than taken from a source. The free bet retention is (o − 1) / o, with the margin-adjusted column computed as (1 / o) × (1 − m) × (o − 1) at m = 0.05. The break-even wagering multiple is 1 / (1 − RTP), and the retained fraction of a deposit bonus is 1 − (1 − RTP) × W. The equivalence column and the 2.71 crossover come from setting those two retained fractions equal and solving for the remaining variable.
Two limits are worth stating plainly. Expected value is an average over many repetitions, and a single bonus or free bet will land far from it in either direction; nothing here predicts an individual outcome. And the 5% margin, the 96% RTP and the 35x requirement are representative figures used to show the shape of the arithmetic, not measurements of any particular offer — substitute the terms in front of you, because those are the only ones that bind. No live odds and no operator terms appear on this page, because prices and promotions change weekly and the formulas do not.
18+ only. A bonus is a marketing cost to the operator, not a source of income for you, and the arithmetic on this page is there to help you value an offer rather than to encourage taking one. Gambling should be entertainment you can afford to lose. Set a deposit limit before you start and use it. If gambling is causing you harm, help is available — see our responsible gambling resources.