TL;DR: A sticky bonus is a casino bonus where the bonus credit itself cannot be withdrawn — only the winnings generated from it — designed to protect the operator from bonus-abuse withdrawal patterns common in non-sticky welcome offers.
What it means
Two operators offer a 100% deposit match up to €100. Operator A grants a "cashable" (non-sticky) bonus: player deposits €100, gets €100 bonus, clears the wagering, and can withdraw the entire €200 balance plus winnings. Operator B grants a sticky bonus: player deposits €100, gets €100 bonus, clears the wagering — but on withdrawal, only the original €100 deposit and any net winnings are paid; the €100 bonus credit itself is removed from the balance.
The sticky construct caps the operator's downside on the bonus instrument. If a player deposits, claims bonus, plays high-volatility slots, wins €600 on a session and withdraws, the operator pays out (€100 deposit + winnings beyond bonus). With a non-sticky bonus, the operator also pays the €100 bonus credit, often producing a negative ROI on that cohort.
How operators measure it
Sticky vs non-sticky bonus performance is benchmarked on three KPIs:
- Bonus completion rate: % of bonus claims that fully clear wagering. Sticky bonuses typically see higher completion (player is incentivised to play through rather than walk).
- Net bonus cost per deposit: (total bonus payout − total bonus-driven NGR) / qualifying deposits. Sticky bonuses usually run 35–55% cheaper than equivalent non-sticky structures.
- Player satisfaction proxies: complaint volume, AskGamblers/Trustpilot rating mentions of "took my bonus". Sticky designs require very clear UX disclosure or they hurt brand long-term.
Why it matters for operators
Sticky bonuses are the standard in regulated EU markets for high-value welcome offers and for VIP reload bonuses. They allow operators to offer headline-friendly bonus amounts (€500 first-deposit match) without the bonus-abuse exposure that comes from non-sticky cash-equivalent instruments.
In the US (NJ, PA, MI), the market norm has shifted toward free bet tokens and deposit-match-with-playthrough rather than sticky bonuses, so US operators using sticky should brand them clearly as "casino bonus credit" rather than "bonus money" to avoid regulatory and consumer-protection scrutiny.
Common pitfalls
- Poor UX disclosure: if the sticky nature is buried in T&Cs, complaints will spike. Surface the "bonus credit cannot be withdrawn" rule on the deposit screen.
- Mixing with high-RTP slots without weighting: a sticky bonus on a 99% RTP table game lets sophisticated players grind down operator edge. Game-weight all bonuses (slots 100%, blackjack 10%, etc.).
- Stacking with cashback or losses-rebate: stacking different cost instruments multiplies operator exposure; bonus engine must enforce single-active rules.
- No max-bet rule during bonus play: without max-bet enforcement, a player can place one €500 spin on a high-volatility slot and bypass wagering math entirely.
Casino welcome bonus design frameworks covers the math and policy detail. Contact Basher to audit your bonus engine and instrument mix.