About BonusWijs
BonusWijs.nl is an independent information platform that makes the mathematics behind Dutch casino welcome bonuses transparent. No hype, no empty promises, just the numbers.
About the author
Maikel Slomp — Ex-iGaming.com engineer, mathematics-driven analysis of Dutch casino bonuses.
Why BonusWijs?
Casinos advertise with "100% up to €250!" and "400 free spins!". But what is that really worth after the wagering requirements? We answer that question with mathematics. We calculate the expected value (EV) of every welcome bonus based on the official bonus terms, so you get a fair picture before making a deposit.
Our approach
Every bonus is manually checked against the official terms on the casino website. We use a mathematical model that accounts for match percentage, wagering requirements, game weighting, RTP and cashout limits. The full methodology is public and explained in plain language.
All bonus data is checked regularly. When terms change, we update the calculations. Each casino page shows when the data was last verified.
Independence
BonusWijs does not offer gambling services and does not receive compensation from casinos for positive reviews. The EV calculation is the same regardless of whether the result is positive or negative. If a bonus is bad, we say so, including a warning on the page.
Who is it for?
BonusWijs is intended for adults (24+) who are considering using a welcome bonus and want to understand its mathematical value. We do not encourage anyone to gamble. The mathematics actually show that the casino always wins in the long run, and that most bonuses cost money.
Recent articles
What is EV (Expected Value) for a casino bonus?
EV is the expected profit or loss from a bonus if you play through all the wagering. In plain language, with the math.
5 min
Wagering explained: the honest math
Wagering requirements determine whether a bonus is profitable. Here is how they work and why they are usually the real trap.
5 min
RTP at online casinos: what does it actually mean?
Return To Player is the average percentage that slots return. Here is why 96% does not mean you get 96% back.
4 min
Free spins bonus: is 'free' actually free?
Free spins look free, but wagering decides whether you can actually cash out. The math, laid bare.
4 min
No wagering bonus: do they actually exist in the Netherlands?
No wagering bonuses barely exist in the Netherlands. What casinos call that is usually something else. Here is what you actually get.
4 min
No deposit bonus: what is it worth without depositing?
No deposit bonuses look like free money, but wagering and cashout caps decide the real value. Here is the math.
4 min
Cashback casino: the bonus that often wins on EV
Cashback returns part of your loss. Unlike match bonuses, there is no wagering on the refund. Here is why the math works in your favour.
4 min
Max cashout on casino bonuses: the cap that cuts your EV
Max cashout limits how much you can withdraw from a bonus. Here is which casinos cap low and how much EV that costs.
4 min
Game weighting: why slots-only rules decide bonus EV
Game weighting decides which share of your wager counts toward clearing. 100% on slots, 10% on table games, 0% on live. Here is what that means for your bonus.
4 min
Which casino bonus to pick: a five-step decision framework
Five questions that decide which bonus fits. Bankroll, variance, wagering, session length, end goal. With calculator links.
5 min
KSA bonus rules: what Dutch casinos can and cannot offer
The Dutch gambling authority (KSA) imposes hard limits on bonuses. Age 24+, no unsolicited offers, mandatory cooling-off periods. Full list here.
5 min
Why Dutch casino bonuses are smaller than their EU counterparts
Dutch bonuses usually sit at €100-€500. Elsewhere in the EU they reach €1,000+. The reason is regulation, tax, and KSA limits.
4 min
Multi-deposit bonus: what a multi-stage welcome package actually yields
888, ComeOn and GetLucky split the welcome across three deposits. Here is what that does to your EV, time, and risk.
4 min
Glossary: casino bonus terminology
Honest definitions for 25 terms around casino bonuses, RTP, wagering, and EV. No marketing speak.
5 min