The casino terms that decide how fast you get paid, how much a bonus is really worth, and which games give the best returns — defined in plain English. Each definition is self-contained, so you can jump straight to the term you need.
RTP (Return to Player)
RTP is the percentage of all wagered money a casino game pays back to players over the long run. A 96% RTP slot returns £96 per £100 wagered on average across millions of spins — not per session. Higher RTP means a lower house edge.
House edge
House edge is the casino's built-in mathematical advantage on a game, expressed as a percentage of each bet it expects to keep long term. Blackjack's edge is about 0.5%; most slots run 1–4%. House edge is the inverse of RTP.
Wagering requirement
A wagering requirement is the number of times a bonus (and sometimes the deposit) must be bet before winnings can be withdrawn. A 30x requirement on a £10 bonus means £300 must be wagered first. Lower is better.
KYC (Know Your Customer)
KYC is the identity verification a licensed casino must complete before paying out, under anti-money-laundering law. It usually requires proof of ID, address, and payment method, and is the most common cause of a delayed first withdrawal.
Withdrawal (cashout)
A withdrawal, or cashout, is the process of moving winnings from a casino account to your payment method. Speed depends on the method (crypto and e-wallets are fastest), KYC status, and the casino's pending period.
Pending period
The pending period is a fixed window (often 0–48 hours) during which a casino holds a withdrawal request before processing it. Some casinos let you reverse the withdrawal during this window and return the funds to your balance.
Max cashout
Max cashout is the maximum amount you can withdraw from bonus-related winnings, often expressed as a multiple of the bonus (e.g. 10x). Winnings above the cap are removed when you withdraw, so it directly limits bonus value.
Volatility (variance)
Volatility, or variance, describes how a slot pays out: high-volatility slots pay rarely but big, low-volatility slots pay often but small. It is independent of RTP — two 96% slots can feel completely different.
E-wallet
An e-wallet is a digital payment account such as Skrill, Neteller, or ecoPayz used to deposit and withdraw at casinos. E-wallet withdrawals are among the fastest non-crypto methods, typically clearing within 24 hours.
Crypto withdrawal
A crypto withdrawal pays winnings out in cryptocurrency (BTC, ETH, USDT) to your wallet. It is usually the fastest cashout method at online casinos, often clearing in minutes once the account is verified and the request is approved.
RNG (Random Number Generator)
An RNG is the certified software that produces random outcomes in online casino games, ensuring each spin or deal is independent and fair. Licensed operators use RNGs tested by independent labs such as eCOGRA or iTech Labs.
Reverse withdrawal
A reverse withdrawal is when a player cancels a pending withdrawal and returns the money to their playable balance. Casinos that allow it during a long pending period make it easier to gamble away winnings — a feature to watch for.
Put it into practice
These terms come together on a few key pages: see the fastest-paying casinos for payout speed, best payout casino games for RTP and house edge, and casino withdrawal times for how cashouts actually work.