With a cashable bonus, completing the wagering requirement converts the bonus into withdrawable money. With a sticky bonus, the bonus amount itself is playable capital only: it inflates your balance while you play and is deducted the moment you cash out. The terms rarely use the word sticky; look for phrasing like 'the bonus is non-withdrawable' or 'removed at withdrawal'.
The distinction changes the offer's value substantially. A 100 sticky bonus is not 100 of value; it is the expected winnings that 100 of temporary capital can generate before its conditions are met, which is far less, and can be negative once the wagering cost is counted.
Why it matters
Two offers advertising the same bonus amount can differ several-fold in value depending on this single clause, and it is one of the least visible clauses in the terms.
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