Bonus Wagering EV, Explained
After reading this you can put a fair dollar value on a casino bonus by subtracting the expected cost of clearing its wagering requirement, and decide whether the offer is worth your time.
What a bonus is really worth
A casino offers you a $100 bonus. That does not mean $100 lands in your pocket. Before you can withdraw it, you must wager the bonus some number of times. A "35x" requirement on a $100 bonus means you must place $3,500 in total bets. Every bet you place is expected to lose a small slice to the house edge, and those slices add up.
The value of the bonus is the face amount minus the total expected loss you incur while clearing it. On a game that returns 96% of what you wager (a house edge of 4%), betting $3,500 costs you about $140 in expected losses. That is more than the $100 bonus. In plain terms, the "$100 free" offer has a negative expected value of about -$40. This calculator does that subtraction for you.
Expected value (EV) is the average outcome if you could repeat the same play many times. A negative EV does not mean you always lose that amount on one attempt. It means that on average, across many identical bonuses, you come out behind.
When to use this, and when not to
Use this calculator when a bonus has a clear cash value, a fixed wagering multiplier, and a game whose RTP you know. Slots publish RTP figures, and table games have known edges. That covers most deposit-match and free-bet promotions.
Do not lean on this model when the terms hide extra friction. Common examples: a maximum cashout that caps your winnings below the bonus, a game weighting rule that makes blackjack count only 10% toward the requirement, or a maximum bet size that stretches the clearing time. Those change the real cost and are covered in the pitfalls section. The formula here gives you the baseline. Read the terms to adjust it.
The formula and the intuition
The house edge per wager is 1 - \text{RTP}. You must wager the bonus times the multiplier. Multiply those together to get the expected cost of clearing, then subtract that from the bonus.
Here B is the bonus amount in dollars, m is the wagering multiplier (for example 35), and r is the RTP written as a decimal (96% becomes 0.96). The term B \times m is the total amount you must wager. The term 1 - r is the fraction of each wager the house keeps on average.
The intuition is short. You get B up front. Clearing it forces you to feed a total of B \times m through a machine that skims 1 - r of everything. If the skim on that turnover exceeds the bonus, the offer is a net loss.
There is a clean break-even condition. Set EV to zero and solve. The bonus pays off exactly when the multiplier equals \frac{1}{1 - r}. At 96% RTP that break-even multiplier is \frac{1}{0.04} = 25. Any requirement below 25x is positive EV on that game; anything above is negative.
Worked example with the demo numbers
A $100 bonus at 35x on a 96% slot
These are the calculator's demo values: bonus = 100, mult = 35, rtp = 96.
- Convert RTP to a decimal:
96% = 0.96. The house edge is 1 - 0.96 = 0.04. - Total wagering required: 100 \times 35 = 3500 dollars of bets.
- Expected cost of that turnover: 3500 \times 0.04 = 140 dollars.
- Subtract from the bonus: 100 - 140 = -40 dollars.
The bonus has an expected value of -$40. On average you lose $40 chasing this offer. Press Calculate with the demo data and you get the same figure.
The result flips sign if any input improves. Drop the multiplier to 20x and the cost becomes 100 \times 20 \times 0.04 = 80, giving EV of +$20. Raise the RTP to 99% (a low-edge game like some video poker or blackjack) and at 35x the cost is 100 \times 35 \times 0.01 = 35, giving EV of +$65.
How the two levers move the value
The multiplier and the RTP fight each other. Higher RTP shrinks the cost of every dollar wagered; a lower multiplier shrinks how many dollars you must wager. The table shows EV on a $100 bonus across common combinations.
| RTP | 20x | 30x | 35x | 40x | 50x |
|---|---|---|---|---|---|
| 94% | -20 | -80 | -110 | -140 | -200 |
| 96% | 20 | -20 | -40 | -60 | -100 |
| 97% | 40 | 10 | -5 | -20 | -50 |
| 99% | 80 | 70 | 65 | 60 | 50 |
Read the 96% row against the demo. At 20x the bonus is worth +$20; at 35x it is -$40. Notice the 99% row stays positive even at 50x, because a 1% edge on $5,000 of turnover is only $50, still below the $100 bonus.
Explore the trade-off
Common mistakes
The single biggest error is ignoring game weighting. Many casinos count slots at 100% toward the requirement but table games at 10% or 20%. If blackjack counts 10%, a 35x requirement effectively becomes 350x of blackjack wagering, which destroys the low-edge advantage. Plug in the effective multiplier, not the headline number.
A high RTP means little if the game is weighted low. A 99.5% blackjack game weighted at 10% forces 10 times the turnover, so its effective edge cost is comparable to a 95% slot at full weight. Always convert the weighting into an effective multiplier before you trust the EV.
Two more traps. A maximum cashout caps your withdrawal, which lowers the real value of the bonus below its face amount, so subtract the cap loss too. And variance is not EV: a positive-EV bonus can still bust your balance before you finish the rollover, especially on high-volatility slots. The number here is an average, not a guarantee.
Related tools
Once you know a bonus is positive EV, size your bets sensibly. The Kelly Criterion Calculator gives the stake that maximizes long-run growth when you hold an edge. To gauge the chance of busting before you clear the rollover, use the Risk of Ruin Calculator. If you are tempted to chase losses with doubling, the Martingale Simulator shows why that raises bust risk without changing EV. And to judge how likely a long dry spell is during clearing, see Streak Probability.
Frequently asked questions
What wagering multiplier makes a bonus break even?
The break-even multiplier is \frac{1}{1-r}. At 96% RTP it is 25x, at 98% it is 50x, at 99% it is 100x. Below that number the bonus is positive EV; above it, negative.
Does a bigger bonus give better value?
Not per dollar. EV scales in proportion to the bonus, so a $200 bonus at the same terms simply doubles the EV of a $100 bonus. The sign never changes with size; only RTP and the multiplier decide whether it is positive or negative.
Why is my $100 bonus worth negative money?
Because the wagering requirement forces enough turnover that expected losses exceed the bonus. At 35x on a 96% game you must bet $3,500, and 4% of that is $140, more than the $100 bonus, so the EV is about -$40.
Should I clear a bonus on the highest RTP game?
Usually yes, but only after accounting for game weighting. A 99% game weighted at 10% often costs more per bonus dollar than a 96% slot weighted at 100%. Use the effective multiplier, not the raw one.
Does this account for hitting a jackpot?
No. RTP already includes the average contribution of jackpots and big wins over the long run. This calculation is an expected value; a single lucky session can beat it, and an unlucky one can fall short.
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