If you’re new to online casinos — or even if you’ve been around a while — the jargon can get confusing fast. From RTP and RNG to wagering requirements and volatility, these terms play a big role in how games work and how bonuses affect your play.
Understanding these terms isn’t just about sounding smart — it’s about making better decisions with your money. This guide breaks down the most important online casino terms you need to know.
Return to Player (RTP)
RTP, or Return to Player, is the theoretical percentage of total wagers a game is expected to pay back to players over time.
- For example: A slot with 96% RTP will, on average, return £96 for every £100 wagered.
- Keep in mind: RTP is calculated over millions of spins — it doesn’t guarantee individual results.
Why it matters: Higher RTP games give you better long-term value, especially for frequent play.
Random Number Generator (RNG)
RNG stands for Random Number Generator, a key piece of software that ensures casino games are fair and unpredictable.
- Every card dealt, dice rolled, or slot symbol spun is determined by the RNG.
- Certified casinos use independently tested RNGs to guarantee fairness.
Why it matters: It ensures that every game result is random and not rigged — essential for trust and legality.
House Edge
The house edge is the opposite of RTP. It represents the mathematical advantage the casino has over the player.
- A game with 96% RTP has a 4% house edge.
- Table games like blackjack typically have a lower house edge, especially with optimal strategy.
Why it matters: The lower the house edge, the better your chances over time.
Wagering Requirements
Wagering requirements (sometimes called rollover requirements) tell you how many times you must bet bonus money before it becomes withdrawable.
- Example: A £100 bonus with 30x wagering = £3,000 in bets before cashout.
- Some bonuses apply wagering to both bonus and deposit, so read terms carefully.
Why it matters: High wagering makes it much harder to convert a bonus into real money.
Volatility (Variance)
Volatility refers to how frequently and how much a game tends to pay out.
- Low volatility: Frequent, smaller wins. Good for longer play sessions.
- High volatility: Rare, larger wins. Ideal for risk-takers or big-win chasers.
Why it matters: It helps match games to your playstyle and risk tolerance.
Max Bet Rules
Some bonuses include maximum bet limits when playing with bonus funds — often around 5% of the bonus amount or a fixed number (e.g., £5).
- Exceeding the limit can void your bonus or winnings.
- Always check bonus T&Cs before spinning high.
Why it matters: It’s a common pitfall for players who accidentally breach the rules.
Game Contribution Percentages
Not all games count equally toward fulfilling wagering requirements.
| Game Type | Typical Contribution |
|---|---|
| Slots | 100% |
| Blackjack | 10–20% |
| Roulette | 10–50% |
| Live Games | Often 0% |
Why it matters: Playing low-contribution games can massively slow your bonus clearance.
Sticky vs. Non-Sticky Bonuses
- Sticky Bonus: The bonus money itself can’t be withdrawn — only the winnings.
- Non-Sticky Bonus: Bonus and winnings can be withdrawn once wagering is completed.
Why it matters: Non-sticky bonuses are more player-friendly, but not always clearly labeled.
Final Thoughts
Online casinos come with their own language — and understanding it can save you time, money, and frustration. Knowing what terms like RTP, RNG, and wagering actually mean gives you more control and a better chance of making the most out of your casino experience.
When in doubt, read the fine print — and if something doesn’t make sense, reach out to support or consult a trusted guide.
18+Â gambleaware.org