Is this bonus worth claiming?
Fill in the offer details from the operator's terms. The verdict and breakdown update as you type.
Quick reference. Most SA casino bonuses use 30–45× wagering on D+B. Slots typically contribute 100%, table games 10%, live casino 0–10%. Online slot RTP averages 96%. Sports free bets at 1× rollover are mathematically different and usually positive EV at SA prices.
Fill in the deposit, match percentage and wagering requirement to see the verdict.
How the maths actually work
Most casino bonus offers are constructed to look generous and play out negatively. The mechanism is the wagering requirement, and the trick is that the requirement applies to either the bonus, the deposit, or both combined, and the player rarely calculates the full implication until after the deposit clears.
The actual expected value of a bonus is a function of five inputs: the bonus amount, the wagering multiplier, what the multiplier applies to, the contribution rate of whatever game you're playing, and the RTP of that game. The calculator above runs those numbers in the order an honest operator would walk you through if they were obliged to disclose them.
The formula in one paragraph
You receive a bonus equal to min(deposit × match%, max cap). The wagering requirement is the multiplier times the wagering base (bonus only, deposit only, or D+B). If the games you intend to play contribute less than 100% (table games and live casino usually do), you need to multiply the wagering total by 100/contribution. That gives you the effective wagering amount. Multiply that by the house edge (100% minus RTP) and you have the expected loss. Subtract the expected loss from the bonus and you have the net EV. Positive net EV means the bonus is structurally worth claiming. Negative net EV means the bonus is a marketing wrapper around a losing proposition.
Why most casino bonuses fail this test
A typical SA casino welcome offer is a 100% match up to R1,000 with 35× wagering on deposit-plus-bonus, slots only. Plug those numbers in. The wagering total is R70,000. The expected loss on slots at 96% RTP is R2,800. The gross value of the bonus is R1,000. The net EV is minus R1,800 per R1,000 deposited. The marketing number was the gross. The maths bill is the net. The same bonus with 25× wagering on bonus-only would be net positive. The same bonus with 35× on deposit-only would be roughly break-even. The structure matters more than the headline.
The sports exception
Free-bet offers in sports are mathematically different. A "stake-not-returned" free bet on a 2.00 line at 1× wagering has an expected value of roughly 50% of the stake amount, because you keep the profit when it wins and lose nothing when it doesn't. The calculator above can model these too if you set rollover to 1, contribution to 100, and "applies to" to bonus only. SA-licensed sportsbooks (Hollywoodbets, Betway, Sportingbet, Supabets, 10Bet) routinely run free-bet promotions that pass this calculation in your favour. Casino welcome bonuses rarely do.
What this calculator does not model
Three caveats. First, variance. The calculation is the expected value over many bonus claims; the actual outcome of any single bonus can vary widely. Second, time. Wagering requirements have expiry windows, and a bonus you can't realistically complete within the window has a value of zero regardless of the EV maths. Third, withdrawal caps. Some bonuses cap the amount you can withdraw from wagered bonus funds, which compresses the actual realisable value below the calculated EV.
For the full editorial framework on how to read SA casino and sportsbook bonuses, read the bonus guide. For where each operator's bonus terms actually live, see our SA-licensed sportsbook comparison. For the bankroll framework that determines how much you should deposit in the first place, the bankroll management guide is the prerequisite read.
Bet responsibly
A bonus is not a reason to deposit. If the math on the offer is positive, that is useful information. The decision to deposit at all should rest on your bankroll, your bet sizing, and what you can comfortably afford to lose. Free 24/7 support: Responsible Gambling Counselling Trust, 0800 006 008. The full responsible gambling guide covers warning signs and support tools.