BonusWijs Audit Methodology
BonusWijs Audit highlights bonus offers from the KSA-licensed Dutch market where the gap between affiliate ranking and Monte Carlo expected value is widest. This page documents the model, the inputs, and the selection rule.
scope
KSA-licensed only
Every operator covered holds an active KSA license under the Dutch Kansspelautoriteit.
model
Monte Carlo, 100,000 runs
Simulated on a 25 euro baseline deposit using each operator's published T&Cs.
selection
largest EV vs. affiliate gap
The bonus with the widest gap between EV ranking and affiliate ranking becomes the Audit subject.
What we measure
For every active welcome bonus on a KSA-licensed casino, we calculate:
- Day-1 spins or bonus value actually delivered on signup
- Bust probability on a 25 euro deposit, across 50,000 simulated sessions
- Expected value on a 25 euro deposit
- Maximum cashout under the bonus T&Cs
- Effective playthrough cost in euros for a typical player
These five numbers replace the single bonus headline most affiliate sites publish.
The model
Monte Carlo simulation, 100,000 runs per offer, 25 euro baseline deposit.
Each run draws from:
- The operator's published wagering multiplier
- What the wagering applies to (bonus only, deposit only, or both)
- Max bet allowed during wagering
- Bonus expiry window
- Max cashout cap, if any
- Game weighting matrix (slots, table games, live casino contribution percent)
- Excluded games list per operator T&Cs
- RTP per game from each provider's official spec sheet
The simulation runs a session as a sequence of spins at the maximum allowed bet, drawn from a normal RTP distribution per game, until the player either clears the wagering or busts the deposit and bonus balance.
Selection rule
An Audit subject is the bonus with the widest gap between:
- Affiliate placement score: averaged ranking across the four largest Dutch casino affiliate sites (top10casino.nl, gambling.com, intikkertje.nl, meneercasino.com).
- BonusWijs EV rank: the operator's place in our EV-ordered list.
The largest gap defines the Audit subject. No editorial pick.
When no offer shows a gap of more than 10 positions, the post is a Clause Check instead: one bonus T&C clause and how it inverts the headline value.
Data sources
- Operator T&Cs: monitored from each KSA-licensed operator's bonus terms page, compared against the prior version to flag changes.
- Affiliate rankings: pulled from the four sites listed above.
- Provider RTP spec sheets: pulled directly from Pragmatic Play, NetEnt, Play'n GO, Microgaming, Yggdrasil and other major providers, refreshed when providers publish updates.
Disputes and corrections
The model assumes published T&Cs are accurate. If an operator believes our reading is wrong, send the corrected T&Cs to corrections@bonuswijs.nl and we re-run the model.
We publish all model inputs alongside each Audit post. If you find a calculation error, the same address.
What we do not measure
- Subjective UX (mobile UI, customer support, deposit speed)
- Loyalty programs or VIP tiers (assessed separately)
- Game library breadth (relevant but not part of EV)
- Operator brand reputation or licensing history
- Affiliate revshare structures (we have no insight into commercial agreements between operators and affiliates)
Why this exists
Most Dutch casino affiliate sites rank by commercial relationship. BonusWijs ranks by what the math says a player can expect to receive. The Audit post series exposes the gap between the two methods.
The gap is not always the operator's fault. Sometimes the affiliate list is just stale. Sometimes the operator changed T&Cs. Sometimes the math genuinely favors an offer that gets ranked low. The point is to make the gap legible, not to assign blame.
Send corrections. Send better math. Send T&Cs we missed. The model gets better with adversarial review.