How we calculate the expected value of an MGA casino bonus
The formula in plain English, the assumptions we use, the worked examples, and the points where the math runs out. Nothing hidden, nothing rounded for marketing reasons.
what's here
The formula, default assumptions, worked examples, free-spin valuation, and where the model stops.
default assumptions
Published RTP, full playthrough, and a conservative read of caps, weighting, and cashout limits.
when this helps
Use this page when you want to understand where our EV scores come from before you compare offers yourself.
What expected value is, in one paragraph
Expected value (EV) is the average amount of money you would keep if you ran a bonus offer through thousands of full sessions. A positive EV means the math is on your side over the long run. A negative EV means it is not. A single session can land anywhere, so EV is what holds up across many plays, not what happens on any one night.
The formula
Every bonus we score runs through the same equation. The effective bonus is what the offer is worth in cash after caps and conditions. The expected loss is what wagering it through eligible games costs on average. The difference is the EV.
core formula
EV = effective bonus − expected loss
effective bonus
The cash you keep after the cashout cap, eligible-games rules, and the bonus type are applied. Always less than the headline amount.
expected loss
Total wagering requirement multiplied by the house edge of the eligible games (1 − RTP). The cost of clearing the bonus on average.
EV
What the offer is mathematically worth in euros after the two sides are subtracted. Positive means a long-run gain. Negative means a long-run cost.
Note: we use the published RTP of the lowest-RTP slot the operator allows on the bonus, not the highest. Wagering is taken at face value from the terms, not rounded down.
Worked examples
negative EV bonus
Offer: 100% match up to €200, 40× wagering on (deposit + bonus), 96% slots, no cashout cap.
Deposit €100. Bonus €100. Combined €200.
Wagering: 40 × €200 = €8,000 in total stakes through 96% slots.
Expected loss: €8,000 × 4% house edge = €320.
EV: €100 − €320 = −€220.
The wagering wipes out the bonus value and then some. The offer is mathematically a paid losing bet.
positive EV bonus
Offer: 100% match up to €100, 25× wagering on bonus only, 97% slots, no cashout cap.
Deposit €100. Bonus €100.
Wagering: 25 × €100 = €2,500 in total stakes through 97% slots.
Expected loss: €2,500 × 3% house edge = €75.
EV: €100 − €75 = +€25.
The bonus value clears the wagering cost with room left over. Rarer than casino marketing implies, but real.
The same math, walked end to end, with every number visible. Use it as a template for any offer you want to check by hand.
A full €100 deposit, step by step
Offer: 100% match up to €100 plus 25 free spins on Book of Dead at €0.20 each. Deposit: €100. Wagering: 30× (deposit + bonus), eligible slots only. Free spins: Winnings carry the same 30× wagering. Slot RTP: 96%.
- Step 1: effective bonusBonus cash: €100. Free-spin value: 25 × €0.20 × 96% = €4.80. Effective bonus before wagering = €104.80.
- Step 2: total wagering30 × (€100 + €100) = €6,000 in total stakes. Free-spin winnings carry the same multiplier separately.
- Step 3: expected loss€6,000 × (100% − 96%) = €240 in expected house-edge cost across the wagering.
- Step 4: net EV€104.80 − €240 = −€135.20.
The headline reads 'double your money plus 25 free spins'. The math reads 'expect to be down about €135 after the wagering'. Both are true. Only one is what you take home.
Where the money actually goes
The same €100 bonus, traced through the wagering cycle. The pattern repeats for every match bonus: cash in, requirement to bet a multiple, expected leakage to the house edge, withdrawable balance at the end.
deposit
€100
bonus credited
+€100
wagering
€3,000
30× the bonus in eligible-slot stakes before any withdrawal is allowed.
expected balance
~€80
Starting €200 minus 4% house-edge cost across €3,000 of wagering. The wagering does the damage, not the bet size itself.
withdrawable
€80
How we value free spins
Free spins look like a freebie. They are not free in EV terms: their value depends on the slot's RTP, the bet size the operator sets, the spin count, and the wagering attached to whatever they win. We collapse the four factors into a single cash figure before scoring.
| Factor | Example | Impact on EV |
|---|---|---|
| Bet per spin | €0.20 (set by the operator) | Multiplies the gross value. Often fixed at the minimum stake, which keeps the gross value small. |
| Slot RTP | 96% | Determines the expected cash return per spin. Lower RTP, lower expected return. |
| Spin count | 50 spins | Scales the gross value linearly. Double the spins, double the gross. |
| Wagering on winnings | 30× the winnings | Reduces the cash value by the house-edge cost of clearing it. Usually the biggest drag. |
our formula
Free-spin value = spins × bet × RTP, then subtract the expected loss of clearing the wagering on the winnings.
Cashout caps cut the upside
A max-cashout cap limits how much of your bonus winnings you can withdraw, regardless of how high your balance climbs. Run €50 of bonus money up to €600 and a €200 cap leaves you with €200. The good outcomes are clipped, the bad outcomes are not. Caps almost always pull EV down.
approximate adjustment
Capped EV ≈ EV(uncapped) × (cap ÷ expected best-case balance)
The real adjustment depends on the probability distribution of session outcomes, which the variance simulator shows in full. In practice, a cap below 5× the bonus is the threshold where EV starts to degrade sharply.
RTP and the house edge
RTP, or Return To Player, is the long-run share a game pays back. A 96% slot keeps 4 cents of every euro wagered as house-edge cost across millions of spins. That number is what we use to calculate how expensive it is to clear a wagering requirement.
Operators publish RTP per game in their lobby. We use the lowest published RTP among the eligible-slot list, not an average and not the highest. Conservative inputs keep the EV from looking better than it actually is.
Note: live tables, blackjack, and roulette often have higher RTP than slots, but they usually contribute less than 100% to wagering (or 0%). The two effects do not cancel. See the table-games section below.
Table games and game weighting
Most bonus terms weight games by contribution to wagering. Slots count for 100%, blackjack often 10%, roulette often 20%, and some tables 0%. A low-edge game cleared at 10% contribution costs roughly as much as a higher-edge slot at 100%, sometimes more. We default to the lowest-edge eligible slot in the calculator, but you can change the input in the bonus calculator to see how a table-game contribution rule flips the EV.
Where the model stops
where the math is solid
- Full-wagering match bonuses with a clearly stated cashout cap.
- Free-spin offers with a fixed bet, a stated RTP, and a single wagering multiple on the winnings.
- Side-by-side comparisons between two offers at the same deposit size.
where the math gets fuzzy
- Tournament leaderboards and prize draws: the payout depends on how other players behave, which we cannot model from one snapshot.
- Loyalty programmes and tiered VIP rewards: the value depends on how often you play at that operator, which we do not assume.
- Cashback on net losses: useful in practice, but the value depends on personal session length and risk appetite, not a single multiplier.
- Hybrid offers that bundle cash, free spins, and a deposit-required prize draw: we score the cash and spins, and flag the rest in the notes.
When an offer falls outside the calculator's defined inputs, we say so on the casino page and exclude the unscored part from the EV. Better to name a gap than to bury it in an assumption.
How we are funded
We do not take affiliate commissions, sponsored placements, or 'preferred operator' fees from any casino we cover. The math does not move because an operator did or did not pay us. If the funding model ever changes, this section is the first place it is documented.
Sources
primary source
Malta Gaming Authority (mga.org.mt) →RTP figures come from each game's published return-to-player disclosure as listed in the operator's lobby. Wagering, cashout, eligibility, and expiry data come from each casino's bonus terms page, re-checked daily by our pipeline.
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Run the math on a specific bonus
The calculator uses every assumption on this page. Change the deposit, the wagering multiple, the RTP, or the cashout cap and watch the EV move in real time.