Why most casino bonuses cost money.
Roughly 95% of welcome bonuses at MGA-licensed casinos have negative expected value. This is not an opinion. It is what the math says when you put the published terms into the EV formula. This guide explains why, and what the 5% exceptions look like.
the rough number
Around 19 in 20 published bonuses at MGA operators land at negative EV. The exact figure shifts as offers rotate, but the ratio is stable.
why so many
Operators tune three variables (WR, RTP, caps) against you simultaneously. The product of three small house-tilts is one large house-tilt.
the exceptions
Positive EV needs low WR, high RTP, no cashout cap, and a deposit floor you can meet. All four, not three.
The claim, in one paragraph
Bonuses are a marketing cost. Operators pay them so they can sit at the top of comparison tables and acquire deposits. The cost is funded by the same revenue source that funds the rest of the business: the house edge on player wagering. For the math to work for the operator, the average bonus across the average player must produce more wagering (at the house edge) than the operator gives away. That means the average bonus has negative expected value for the player. The 95% figure is what falls out when you check the actual offers against the actual terms.
Three tilts, one negative EV
The operator has three independent ways to tilt a bonus against you. Most use all three at once. Each one alone is mild. Stacked, they are decisive.
tilt 1: WR multiplier
Higher multiplier means more wagering. More wagering at the house edge means more expected loss. See the WR guide.
tilt 2: low RTP eligible games
Restricting WR to slots forces you onto a 4% to 8% house edge instead of the 0.5% to 2.7% you could find on table games. See the RTP guide.
tilt 3: cashout cap
Capping the withdrawal clips your upside but not your downside. The asymmetric clip pulls EV negative. See the cashout caps guide.
A bonus with a moderate WR (35x), default RTP (96% slots), and a cap (€100 on €100 bonus) is the modal MGA offer. Worked through the formula, it lands around −€40 to −€80. That is the average.
A typical negative-EV bonus, fully worked
modal offer
100% match up to €100, 35x WR on bonus, 96% RTP slots, €100 cashout cap
Step 1. Wagering = 35 × €100 = €3,500.
Step 2. Expected loss = 4% × €3,500 = €140.
Step 3. Effective bonus, ignoring the cap, = €100.
Step 4. The cap clips withdrawal to €100. In sessions where you win more than €100, the excess is lost. This further reduces the effective bonus by roughly €15 to €25 in expectation (depending on volatility).
Step 5. EV ≈ (€100 − €20) − €140 = −€60.
This is what the market average looks like. The "free €100" is a €60 expected payment from the player to the operator. That is the business model.
What the 5% looks like
Positive-EV bonuses exist. They appear when an operator is willing to pay above market to acquire a deposit (during launch, a market entry, or a regulatory window where they need volume fast). The shape is consistent.
recipe for positive EV
low WR (≤25x) + high RTP (≥97%) + no cashout cap + reachable deposit
positive EV example
100% match up to €200, 20x WR on bonus, 97% RTP slots, no cap
Step 1. Wagering = 20 × €200 = €4,000.
Step 2. Expected loss = 3% × €4,000 = €120.
Step 3. Effective bonus = €200 (no cap, no clip).
Step 4. EV = €200 − €120 = +€80.
The structural change is all four levers moving the right way at once: low WR, high RTP, no cap, full bonus amount. Two of four is common. Three is rare. Four is the 5%.
A 30-second triage checklist
You do not need a calculator to spot a likely loser. Run any bonus through these questions in order. A "no" on the first three is usually fatal.
- Is the WR multiplier 35x or less? Above 40x and the bonus is almost certainly negative EV regardless of the other terms.
- Does the WR apply to bonus only? If it applies to bonus + deposit, double the wagering total in your head before continuing.
- Are slots at 96% RTP or better available? If you are forced onto a single low-RTP game, the house edge is bigger than the formula assumes.
- Is there a cashout cap? A cap below 2x the bonus amount makes even a low-WR offer expensive.
- Is the time window long enough? 30 days is comfortable. 7 days forces high-bet, high-variance play that increases the chance of busting.
If three of five are positive, the bonus is worth running through the full EV calculation. If three or more are negative, skip it.
Negative EV is not always wrong
A negative EV bonus is not a scam. It is a paid entertainment product, the same way a cinema ticket is. The number tells you the price, not whether to buy.
A −€20 EV bonus that gives you a few evenings of slot play is cheaper than most subscription services. A −€200 EV bonus is the cost of a hotel night. Decide whether the experience is worth the expected price. The math just makes the price visible.
Where the math earns its keep is in the comparison. Two offers can look similar and price out €60 apart. The EV number is the only honest way to tell which side of that €60 you are on.