The rule exists because large stakes are the fastest way to gamble a bonus through its requirement: one big win can clear the conditions in a handful of rounds, which breaks the economics the operator planned. Capping the stake, commonly at around 5 per round or a small share of the bonus, forces the requirement to be ground out across many rounds, where the house edge does its work.
Enforcement is usually automatic and retroactive: a single spin above the cap flags the account, and the bonus with everything it won is removed at withdrawal time, often after days of play. It is among the most disputed clauses in gambling, and among the most consistently upheld, because it is written in the terms.
Why it matters
It is the clause most likely to erase real winnings from a player who was not trying to abuse anything. If a bonus is active, the maximum stake is the first term worth knowing by heart.
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