Frequently asked questions
Answers to the most common questions about BonusWijs.nl and our calculations.
What is BonusWijs.nl?
BonusWijs.nl is an independent information platform that calculates the expected value (EV) of welcome bonuses at licensed Dutch online casinos. We use mathematics to show what a bonus is really worth after wagering requirements.
What is expected value (EV)?
Expected value is the amount a bonus earns or costs you on average, expressed in euros. A positive EV (+€51) means the bonus offers a mathematical advantage. A negative EV (−€20) means you lose money on average. The calculation takes into account the bonus value, wagering requirements, RTP and game weighting.
How do you calculate EV?
The formula is: EV = effective bonus − expected loss. The expected loss is the total wagering requirement × the house edge (1 − RTP). We use the RTP published by the casino, not the theoretical maximum RTP from the provider. See our methodology page for the full explanation.
Are your calculations exact?
Our calculations are mathematical estimates based on the official bonus terms. They assume a constant bet per spin and do not account for bonus features that change variance. The actual result per session can vary significantly due to luck (variance), but over many sessions it converges toward the EV.
Can I make money with casino bonuses?
Most casino bonuses have a negative expected value: you lose money on average. A small number of bonuses (especially free spins without wagering requirements) have a positive EV. But even with a positive EV, that does not guarantee a profit per session. The casino always has a mathematical edge on the games themselves.
Why does the site say 24+?
Dutch law (Kansspelautoriteit) requires that bonuses and promotions may only be shown to players aged 24 and over. Players between 18 and 23 may gamble but cannot participate in bonus offers.
How often is the data updated?
All bonus data is regularly checked manually against the official terms on the casino website. Each casino page shows the date of the last check. Our system automatically alerts when data is older than 30 days.
Do you offer gambling services?
No. BonusWijs.nl is purely an information platform. We do not offer gambling services, accept deposits or manage player accounts.
What is the difference between wagering on 'bonus' and 'bonus + deposit'?
With wagering on 'bonus', only the bonus amount is multiplied (e.g. 30× €100 bonus = €3,000). With 'bonus + deposit', the bonus and deposit are added together (e.g. 30× (€100 bonus + €100 deposit) = €6,000). The second type is significantly more expensive: you have to wager twice as much.
Why do some casinos have a warning on their page?
Casinos with an expected value worse than −25% of the deposit automatically receive a red warning. This means the wagering requirements are so high that you lose a large portion of your deposit on average. We always recommend reading the terms carefully before accepting a bonus.
What is the difference between wagering on bonus versus wagering on deposit?
With wagering on bonus the requirement applies only to the bonus amount. With wagering on deposit your own deposit counts too, and sometimes both added together. A 30x requirement on a €100 bonus is €3,000 to roll over. That same 30x on bonus plus deposit is €6,000, exactly double the expected loss.
What is game weighting or game contribution?
Game weighting is the percentage at which a game counts toward the wagering requirement. Slots usually count 100%, roulette often 10% and blackjack sometimes 0%. Wagering €100 on a game with 10% weighting only counts as €10 toward the requirement. Read the terms, because this is where casinos hide a lot of cost.
What happens if I don't meet the wagering requirement in time?
The bonus and any winnings from it expire. Your own deposit stays yours unless the terms say otherwise, but all outstanding bonus funds and winnings derived from them disappear. Most Dutch casinos use 30 to 90 days. Check the window before you accept, especially when the wagering requirement is high.
Can I cancel a bonus if I change my mind?
Yes, at virtually every KSA-licensed casino you can cancel a bonus. Your own deposit stays and you can usually withdraw or play it without a wagering requirement. Winnings already made with bonus money are typically forfeited on cancellation. Contact customer support or use the option in your account settings.
How long does a payout take at Dutch casinos?
Typically 0 to 3 business days after verification. iDEAL and Trustly are often processed within 24 hours, bank transfers usually take 1 to 3 business days. Your first payout may need an extra day for identity checks. Casinos that take longer than 5 business days stand out in our bonus analysis.
Do I pay tax on casino winnings in the Netherlands?
At a KSA-licensed casino the operator pays gambling tax on your behalf, so the amount you withdraw has it already handled. Play at a foreign casino without a Dutch licence and you must declare gambling tax yourself on anything above €449 per month. The rate rose to 34.2% in January 2026. Check with the Belastingdienst if in doubt.
What is the difference between bonus money and real money in my account?
Real money is your deposit and cashed-out winnings, withdrawable without conditions. Bonus money is tied to the wagering requirement and can only be withdrawn once that is met. Many casinos wager your real money first before touching the bonus. Check your account overview to see which part is bonus and which is cash.
What is max cashout and should I check it?
Max cashout is the cap on what you can withdraw from a bonus, regardless of how much you win. If you get €100 free spins, win €600, but the cashout limit is €100, you receive €100 and the rest expires. Always check this, especially on no-deposit offers. It can reduce a positive EV on paper to almost nothing.
Why does a casino ask for my BSN or ID?
It is a legal requirement at every KSA-licensed casino. The Kansspelautoriteit demands that operators verify your identity, age and the CRUKS register before you can play. Your BSN is used for the CRUKS link and for gambling tax. A casino that skips verification does not hold a Dutch licence, and that is a red flag.
What is CRUKS and how does it work?
CRUKS is the Dutch national gambling self-exclusion register. You can register voluntarily, or be registered by a family member or the Kansspelautoriteit. Once on CRUKS, every KSA-licensed casino and arcade blocks you immediately. The minimum period is six months. Sign up via cruks.nl using DigiD.
What does a KSA licence mean and how do I check if a casino has one?
A KSA licence means the casino is approved by the Kansspelautoriteit and follows Dutch rules on fairness, payouts and responsible gambling. kansspelautoriteit.nl publishes a public list of all licence holders. Every legal casino also shows the KSA logo in its footer. Without a licence you pay gambling tax yourself and have no consumer protection.
Why are bonuses only available from age 24 in the Netherlands?
Dutch law prohibits casinos from showing bonuses and promotions to players under 24. You can gamble from 18, but anything promotional sits behind a 24+ gate. The reason is harm reduction: young adults are more vulnerable to gambling behaviour. Casinos that break this rule risk their licence.
How current is the bonus data on this site?
Every casino page shows the date of its last check. We verify bonus terms manually against the official casino site on a regular schedule. Our system flags anything older than 30 days. If you spot a difference between BonusWijs and the casino site, the casino site is authoritative and we want to know at info@bonuswijs.nl.
Why is a casino's score sometimes negative?
A negative score means the bonus mathematically costs money on average. The effective bonus is smaller than the expected loss you incur while rolling it over. With a 40x requirement on bonus plus deposit and 96% RTP slots, expected loss quickly exceeds the bonus itself. A negative score is not a judgement on the casino overall, only on this specific bonus.
Do you use affiliate links?
No. BonusWijs has no affiliate links, no commission deals, no advertisers and no sponsors. Every casino link on the site goes directly to the operator without tracking parameters. The site is self-funded, so rankings are driven by expected value and not by what an operator pays.
What is the difference between expected value and actual winnings?
Expected value is the mathematical average over countless sessions, actual winnings are what you end up with in a single session. A bonus with an EV of +€20 may deliver you +€200 one time, −€80 another. Over hundreds of sessions the average converges to the EV. Short-term variance is large, so do not treat EV as a per-session guarantee.
Which bonus do you pick with only a €20 deposit?
Look for a bonus with a low minimum deposit and a low or zero wagering requirement on the spins. Free spins with cash winnings are usually mathematically better at a €20 deposit than a match bonus with high wagering. Our bonus analysis per casino shows which offers work from €10 or €20. High match percentages have little impact at this deposit size.
Can I claim multiple welcome bonuses at the same operator?
No, one welcome bonus per player per casino. KSA-licensed casinos link your BSN to the account and detect duplicates immediately. You can take a welcome bonus at each different licensed operator, which means around 30 different offers on the Dutch market. After the welcome bonus there are often reload and loyalty offers, but those count separately.
What is slot variance and why should I care?
Slot variance is how much a slot's outcomes deviate from the average. Low variance means frequent small wins, high variance means rare big wins with long losing stretches in between. For a wagering requirement low variance is often calmer, because your balance moves down or up more steadily. For fun and big wins high variance is better, provided your balance survives the dry spells.
Are higher match percentages always better?
No. A 200% match bonus with 40x wagering on bonus plus deposit often has a worse expected value than a 100% match bonus with 25x on the bonus alone. The match percentage sets how large the bonus becomes, but the wagering requirement sets what you must do to unlock it. Both together, plus the RTP, determine the final EV.
Can't find your question? Contact us at info@bonuswijs.nl.
Want to know more about our calculations? Read the methodology.