“200% up to $500” sounds generous — until you do the math on the wagering requirements. In this article we share the formula reviewers use to score casino bonuses, and we apply it to three offers from our bonus table.
The formula: expected value of a bonus
The real value depends on three things: bonus size, wagering requirement, and the RTP (return to player) of the eligible slots. A simplified version:
Real value = Bonus − (Wagering × (1 − RTP))
Example: $100 bonus, 35x wagering, slot at 96% RTP → $100 − ($100 × 35 × 0.04) = −$40. On average you lose $40 while clearing it — even if everything goes smoothly.
Three offers compared
Sankra Casino — 200% up to $7,500, 30x wagering
At full take-up: $7,500 − ($7,500 × 30 × 0.04) = −$1,500. The bonus is headline-grabbing, but the wagering eats the value.
Wildsino — 100% up to $2,000, 25x wagering
$2,000 − ($2,000 × 25 × 0.04) = $0. A statistically neutral offer — fun play at no expected cost.
MoonWin — 100% up to $6,500, 20x wagering
$6,500 − ($6,500 × 20 × 0.04) = +$1,300. One of the rare offers with a positive expected value, thanks to the lower wagering.
Things to also watch for
- Max bet rule — most bonuses cap stakes at $5/spin while wagering. Exceed it and winnings are voided.
- Time limit — under 7 days at 35x is almost impossible to clear.
- Game weighting — only slots usually count 100%. Table games often count 5–10%.
Bottom line
The biggest bonus is rarely the best. Filter our bonus comparison by wagering ≤ 25x — and check that the operator is properly licensed before depositing.