Casino bonus glossary A–Z
Every term you meet in casino bonus terms and conditions, defined in plain English with worked pound examples.
By the Top Casino Bonus team. Last checked .
Casino bonus glossary: the words in bonus terms, defined
This casino bonus glossary defines the words you meet in UK bonus terms, from everyday ones like wagering and expiry to the more technical vocabulary of verification, safer gambling and dispute resolution. Each entry opens with a one-sentence definition, then explains how the term works, gives an example in pounds, shows where it usually appears in a set of terms and links to related entries.
Bonus terms are often short on space, so a single word can carry a lot of meaning. ‘Sticky’ tells you whether the bonus itself can ever be withdrawn. ‘Contribution’ tells you how much of each bet counts towards wagering. ‘Max cashout’ caps what you can take out however much you win. Knowing these words before you opt in is the simplest way to avoid a surprise later.
The glossary is educational and doesn't promote offers. Definitions follow the Gambling Commission's own usage where it has one, and say so where everyday casino language differs from the official wording.
You don't need to read it from A to Z. Most people arrive with one word they've just met in a set of terms, read that entry, and follow a link or two to the words around it. The table of core terms below is the shortlist worth knowing before your first bonus.
Ten casino bonus glossary terms to know first
| Term | Plain definition | Example |
|---|---|---|
| Playthrough | The total you must bet before bonus winnings become withdrawable; also called wagering | £20 bonus × 10 = £200 of bets |
| Contribution percentage | The share of each bet that counts towards wagering | A £10 bet at 10% counts as £1 |
| Sticky bonus | A bonus that can be played with but never withdrawn itself | Only winnings above the bonus amount can be cashed out |
| Max cashout | A cap on what can be withdrawn from bonus winnings | A £1,000 cap on a balance that reached £1,400 |
| Match percentage | How much the casino adds relative to your deposit | 50% of a £40 deposit = £20 bonus |
| Qualifying deposit | The deposit that triggers an offer, often with a minimum and excluded methods | A £10 deposit by an allowed method |
| Coin value | The stake per spin on free spins | 100 spins at 10p = £10 of spins |
| Validity period | How long a bonus or spins last once credited | Spins valid for 7 days |
| House edge | The long-run share of stakes a game keeps | 4% of £200 wagered = about £8 on average |
| Significant terms | The key restrictions that must be shown with an offer | Minimum deposit, wagering, expiry, excluded methods |
Every figure in the examples is an illustration. Averages such as the house edge describe what happens over a very large number of bets; a single session can come out well ahead or behind.
Terms A–Z
How the casino bonus glossary is organised
The cards below are grouped by where a term appears in the life of a bonus. Each group mixes common words with the less obvious ones that tend to cause disputes.
| Group | Terms in this group include | Start with |
|---|---|---|
| Claiming | Qualifying deposit and bet, first deposit, claim window, auto-claim, opt-in, voucher code | Claim window |
| Playing | Bonus balance, locked funds, wagering progress, stake contribution, minimum stake, selected games | Bonus balance |
| Withdrawing | Bonus conversion, pending withdrawal, withdrawal limit, payout time, bonus forfeiture | Bonus forfeiture |
| Checks | KYC, proof of address, source of funds, net and gross deposit | KYC |
| Fair play | Irregular play, multi-accounting, bonus abuse, one offer per household | Irregular play |
| Safer gambling | Deposit limit, reality check, time-out, cool-off, self-exclusion, GAMSTOP | Deposit limit |
| Game maths | RTP, volatility, expected value, turnover, game round | RTP |
Some words appear in more than one group because they matter at more than one stage. A net deposit, for example, is part of how a casino's financial checks work, but it also explains how some cashback offers measure losses. Where that happens, each entry says which sense it covers and links to the other. Words that casinos use for their own branded features, such as a named rewards scheme, are explained in general terms only, because their rules belong to the casino and can change.
Official wording and everyday casino language
Casinos, players and the regulator don't always use the same words. The Commission's glossary of terms for its consumer guidance (opens in a new tab) defines wagering requirements as any requirement to make wagers totalling a particular value before funds become withdrawable, and significant terms as the key restrictions that apply to a promotion. It also uses ‘mixed wager’ for a bet drawn from both your deposit and bonus balances.
- ‘Bonus abuse’ is casino language. Official guidance talks instead about irregular play and prohibited types or patterns of play, which must be spelled out in the terms; see the Commission's page on promotional play restrictions (opens in a new tab).
- ‘Affordability checks’ is a popular phrase the Commission calls inaccurate. What exists is a financial vulnerability check at £150 of net deposits in 30 days; credit-reference financial risk assessments are not live.
- ‘Deposit limit’ now has a narrow meaning: only gross limits, which count every deposit, may use that name.
- ‘Incentive’ is the regulator's word for what casinos call a bonus or promotion; the incentive entry explains the overlap.
Where terms are ambiguous, the Consumer Rights Act 2015 says the meaning most favourable to the consumer applies. That makes definitions more than a matter of vocabulary.
Terms whose meaning changed in 2025 and 2026
A few glossary entries describe things that work differently now. From 19 January 2026, playthrough can't exceed 10 times the bonus, so entries on wagering, sticky bonuses and expected value use 10x in their examples. The same date ended incentives that mix products, which affects how ‘welcome offer’ and ‘promotion’ are used.
- 28 February 2025: the net deposit threshold for financial vulnerability checks fell from £500 to £150 in a rolling 30 days; see net deposit.
- 1 May 2025: marketing consent is given per product (betting, casino, bingo) and per channel (email, SMS, phone).
- 31 October 2025: a financial limit prompt before the first deposit made setting a limit the default.
- 30 September 2026: casinos had until this date to offer gross deposit limits; see gross deposit.
Support terms changed too. GambleAware closed on 31 March 2026, according to trade reports, so the glossary points to the National Gambling Helpline (0808 8020 133), GamCare, GAMSTOP and NHS services instead.
How to use the glossary with a set of bonus terms
- Open the offer's significant terms next to this page.
- Underline every word you couldn't explain to someone else in one sentence.
- Look each one up and note the number it refers to, such as the multiple, cap or deadline.
- Follow the related-term links, because terms such as max cashout and sticky bonus often work together.
- If a term seems unfair or unclear, read the matching page in the UK casino bonus rules hub before you opt in.
For a longer walk through real wording, the bonus terms guide reads a typical set of UK terms line by line, and the casino bonus questions hub answers the practical questions that definitions raise. The ASA's guidance on promotional terms and conditions (opens in a new tab) explains what advertisers must make clear.
Frequently asked questions
What does wagering mean in casino bonus terms?
Wagering, also called playthrough, is the total amount you must bet before bonus winnings become withdrawable. It is written as a multiple of the bonus, so a £20 bonus with 10x wagering needs £200 of bets. In Great Britain the multiple can't exceed 10x, a cap in force since 19 January 2026. Your own deposit is never subject to wagering. Bets on some games may count only in part, depending on the contribution rate. The playthrough entry has more examples.
What is the difference between a sticky and non-sticky bonus?
A sticky bonus can be played with but never withdrawn itself; when you cash out, the bonus amount is removed and only winnings above it can be withdrawn. A non-sticky bonus keeps your cash and bonus separate, so you play with your own money first and the bonus only comes into play if that runs out. If you win on your cash, you can usually withdraw and walk away. The non-sticky bonus entry explains why many players prefer it.
What does max cashout mean?
Max cashout is a cap on how much you can withdraw from winnings made with a bonus, however large the balance grows. If the cap is £1,000 and wagering leaves you with £1,400, only £1,000 can be withdrawn and the rest is removed. Not every bonus has one, and no-wagering spins usually don't, but deposit matches often do. The cap must be shown as a significant term. Our fair max cashout question discusses typical figures.
What is a contribution percentage?
A contribution percentage is the share of each bet that counts towards wagering. Slots commonly count at 100%, while table games, live casino and some other games may count at a lower rate or not at all. If blackjack contributes 10%, a £10 hand counts as £1 towards your wagering total, so clearing the same requirement takes ten times as much play. Each casino sets its own rates in the bonus terms. See our game weighting guide for worked examples.
What is the difference between RTP and house edge?
They are two sides of the same figure. RTP, or return to player, is the share of all money staked that a game pays back over the long run; house edge is the share it keeps. A slot with a 96% RTP has a 4% house edge, so across very large numbers of spins it keeps about £4 of every £100 staked. Neither predicts a single session, which can vary widely. Casinos may run different RTP versions of one game, so check the help screen.
What does KYC mean for a casino bonus?
KYC stands for know your customer: the checks a casino runs to confirm your name, address and date of birth. In Great Britain they must be completed before you can deposit or gamble, including with a bonus, a rule in force since May 2019. Most checks happen automatically using databases; you may be asked for documents if they don't match. A casino can't use a withdrawal request to ask for ID it could have asked for earlier. Our KYC entry explains the documents usually requested.
Is bonus abuse an official term?
No. ‘Bonus abuse’ is casino and industry language. Gambling Commission guidance talks about irregular play and prohibited types or patterns of play, and it says casinos must spell those out clearly in their terms in advance. A casino can't keep sole discretion to decide after the event what counts as a breach. Common examples in terms include opening multiple accounts or using someone else's details, both of which void winnings. The bonus abuse entry covers how casinos define it.
What does validity period mean compared with claim window?
The claim window is how long you have to accept an offer once it becomes available, such as 48 hours. The validity period is how long the bonus or spins last once accepted, such as seven days. Miss the claim window and the offer lapses; miss the validity period and any unused spins or unfinished bonus funds are removed. Both are significant terms and should be shown with the offer. Our bonus expiry guide explains common time limits.
Where can I find the official definitions of bonus terms?
The Gambling Commission publishes a glossary alongside its guidance on fair and transparent terms, which defines wagering requirements, significant terms, play restrictions and mixed wagers. The ASA and CAP publish guidance on what promotions must make clear, and the Consumer Rights Act 2015 sets the fairness test for terms. Casinos also define their own words in their general terms. Our entries follow official usage where it exists. The significant terms entry is a good example of how the two fit together.