Bonus Wagering Math: How Playthrough Requirements Work
A welcome bonus banner leads with two numbers — a percentage match and a dollar cap — and those are the easy part to understand. The number that determines whether a bonus is worth claiming sits one click deeper, in the terms: the wagering requirement, sometimes called a playthrough multiplier. It's the single biggest factor in whether bonus funds convert into real, withdrawable money, and it's worth understanding the arithmetic before opting into any offer.
What a Wagering Multiplier Means
A wagering requirement is expressed as a multiplier — commonly written as 25x, 35x or similar — applied either to the bonus amount alone or to the bonus plus your deposit combined. Say a $100 bonus carries a 30x requirement on the bonus amount: you would need to wager $3,000 in total bets across eligible games before that bonus, or any winnings from it, becomes withdrawable. That number can look abstract until it's translated into session terms — at an average bet of $2 per spin, $3,000 in wagering means roughly 1,500 spins before the bonus clears, regardless of whether your balance goes up or down along the way.
| Wagering base | What it means |
|---|---|
| Bonus-only (e.g. 30x bonus) | Multiplier applies just to the bonus amount, not your own deposit |
| Bonus + deposit (e.g. 30x b+d) | Multiplier applies to the combined total — a noticeably larger wagering figure for the same multiplier |
The difference between those two bases matters more than the multiplier number itself. A 30x bonus-only requirement on a $100 bonus is $3,000 in wagering; a 30x bonus+deposit requirement on that same $100 bonus with a $100 deposit is $6,000 — double the play, same headline "30x".
Game Contribution Rates
Not every wager counts equally toward clearing a requirement. Slots typically contribute 100% of each bet toward wagering, while table games like blackjack and roulette are frequently weighted much lower — sometimes 10% or less — because they carry a lower house edge and would otherwise let a bonus clear too cheaply. Live dealer games often carry their own separate, usually low, contribution rate. This is exactly why a table-games specialist can find a bonus far less useful than a slots player claiming the identical offer: the headline multiplier is the same, but the effective play required to clear it is not.
Worked Example: Duospin's Published Package
Duospin's homepage advertises a Casino Welcome Package of 350% up to $4,500 plus 400 free spins. What the homepage banner does not show is the wagering requirement or the game-contribution table — those sit in the promotion's own terms rather than on the banner, which is common practice and not unique to this operator. That gap is a useful example in itself: a bonus percentage alone tells you nothing about how hard it is to withdraw, so treat any headline match rate — Duospin's or anyone else's — as step one of the calculation, not the whole answer. Before opting into a package like this, the terms page is where the real numbers — multiplier, contribution rates, maximum bet while a bonus is active, and expiry window — live.
Other Terms That Change the Math
- Maximum bet while wagering — many bonuses void themselves if you place a single bet above a set cap while clearing the requirement, so check this before increasing your stake mid-session.
- Time limit — most bonuses expire, often within 7 to 30 days, whether or not you've cleared the wagering by then.
- Withdrawal cap — some offers cap how much of the winnings from bonus play can be withdrawn, separate from the wagering requirement itself.
- Excluded games — a small number of high-RTP or jackpot titles are commonly excluded from counting toward wagering entirely.
A Quick Way to Judge Any Offer
Before claiming a bonus, three questions cover most of what matters: what's the multiplier, and is it on the bonus alone or bonus plus deposit; what do the games you play contribute toward it; and is there a time limit you can realistically meet at your normal pace of play. If any of the three isn't published where you'd expect, the terms page is the place to look — not a third-party summary. The same logic applies to weekend tournament prizes and reload offers, covered in our weekend promo guide, since a won prize can carry its own separate wagering on top.
None of this is a reason to avoid bonuses outright — a well-understood offer with reasonable terms genuinely adds value on top of a session you were going to play anyway. It's simply a reason to read the multiplier before the match percentage, since the multiplier is what determines whether that match ever becomes real money. Current offers and terms for Duospin specifically are on the Duospin bonus page.