Bonus math — why 35× wagering kills the EV.
A €100 "100% bonus + €100 free spins" looks like €200 of upside. The wagering requirement does the actual math. PUTKI HQ runs the EV by hand so you can read a T&C in 30 seconds.
The one-line EV formula
For a cashable bonus on a slot with RTP r and wagering requirement w on (deposit + bonus):
EV = (deposit + bonus) × (1 - (1 - r) × w) - deposit
Concretely: a €100 deposit + €100 bonus with 35× wagering on a 96% RTP slot gives EV = €200 × (1 - 0.04 × 35) - €100 = €200 × (-0.40) - €100 = -€180. That is the expected outcome.
| Wagering × | RTP | Net EV on €100+€100 |
|---|---|---|
| 15× | 97% | +€10 |
| 20× | 97% | -€20 |
| 25× | 96% | -€100 |
| 35× | 96% | -€180 |
| 40× | 96% | -€220 |
| 50× | 95% | -€400 |
Read the bonus type first
Cashable: the bonus amount stays in your balance after wagering is cleared. Sticky: the bonus disappears at withdrawal — you only keep winnings above the bonus. A sticky bonus is mathematically a free shot with bounded upside; never treat it as deposit value. Hybrid sticky (a.k.a. "phantom") bonuses subtract the bonus from your balance at cashout — the difference matters once you do real arithmetic.
Five lines in any T&C that destroy value
- Wagering on (deposit + bonus), not just bonus.
- Max bet during wagering < €5 — easy to forget, instant void.
- Game weighting: blackjack at 5%, slots at 100% — kills any low-edge strategy.
- Max cashout cap (e.g., 5× bonus) — bounds your upside while leaving downside open.
- Bonus expiration < 14 days — forces play volume.