News · United Kingdom
How to Read a Casino Bonus: the Arithmetic Behind Wagering, Max Bet and Excluded Games
A bonus headline is a number without a unit. “100% up to £100” tells you what you receive and nothing about what you must do to keep it. The four terms that decide that are the wagering multiplier, the base it is applied to, the maximum stake while the bonus is live, and the list of games that do not count.
Great Britain changed one of those four in January 2026, and the change is large enough that older explainers are now describing a market that no longer exists here.
What changed on 19 January 2026
The Gambling Commission announced new rules on promotions on 26 March 2025, amending Social Responsibility Code Provision 5.1.1 (Rewards and bonuses). Two elements matter:
- A cap on wagering. The final wording is that licensees must not “apply wagering requirements to incentives, which require customers to play through bonus funds, over a maximum of 10 times” (Gambling Commission — Proposal 1: ban or limit the use of wagering requirements). The Commission considered and rejected both a full ban and lower caps of 1x and 5x.
- A ban on mixing products. Licensees “must not include more than one type of gambling product (betting, casino, bingo and lottery) within an incentive” (Gambling Commission — Proposal 2).
Both came into force on 19 January 2026, a date moved from the originally announced 19 December 2025 (Gambling Commission — Gambling promotions to be safer and simpler).
Note precisely what the cap is measured against: bonus funds, played through a maximum of ten times. Terms elsewhere in the world are frequently expressed as a multiple of deposit plus bonus, which is a different and much larger base for the same headline number.
The arithmetic, on a specific example
Take a £50 deposit with a 100% match, giving £50 of bonus funds.
| Base of the multiplier | Multiplier | Turnover required | |
|---|---|---|---|
| GB cap since 19 Jan 2026 | Bonus funds only (£50) | 10× | £500 |
| Common older/offshore structure | Deposit + bonus (£100) | 35× | £3,500 |
Turnover is not loss — it is the total you must stake, recycling the same money repeatedly. What it costs you on average is the house edge applied to that turnover. On a slot with a 96% return to player, the edge is 4%:
- £500 of turnover → expected cost £20
- £3,500 of turnover → expected cost £140
Against £50 of bonus funds, those are two entirely different products wearing the same headline.
Two cautions on that arithmetic, because they are the difference between a calculation and a promise. First, “expected” is a long-run average across an enormous number of spins; your individual result will sit somewhere on a wide distribution and is more likely to be worse than the average than better on a sample this small. Second, the expected cost assumes every condition can actually be satisfied, which is what the next three terms decide.
The three terms that quietly do the work
Maximum stake while a bonus is active. Typically £5 or lower, and breaching it is usually grounds for voiding the bonus and everything won with it. This interacts with a separate legal limit: since 9 April 2025 the maximum stake per game cycle on online slots in Great Britain is £5 for players aged 25 and over, and since 21 May 2025 it is £2 for players aged 18 to 24, under The Gambling Act 2005 (Operating Licence Conditions) (Amendment) Regulations 2025.
Game weighting and exclusions. Slots commonly contribute 100% of stakes toward wagering; roulette, blackjack and live dealer tables often contribute 10%, 5% or nothing. A £500 requirement on a table game contributing 10% is a £5,000 requirement in practice. Individual high-RTP titles are also frequently excluded outright, precisely because their edge is thin.
Expiry. A wagering requirement with a deadline is a rate, not a total. £500 of turnover at £0.50 per spin is 1,000 spins. Since RTS 14D requires that “it must be a minimum of 2.5 seconds from the time a game is started until the next game cycle” (Gambling Commission — RTS 14), 1,000 spins is at least 2,500 seconds — about 42 minutes of uninterrupted play, and realistically longer. Check that against a seven-day expiry before assuming the requirement is small.
A five-minute reading checklist
- Find the multiplier and its base. Ten times bonus and ten times deposit-plus-bonus differ by a factor of two or three.
- Multiply it out into a cash turnover figure. Do not reason in multiples.
- Multiply turnover by the house edge of the games you will actually play to get the expected cost.
- Find the maximum stake clause and check it against how you normally bet.
- Find the excluded and weighted games list. Divide your turnover requirement by the weighting.
- Find the expiry and convert it to spins per day.
- Check what happens to the bonus if you withdraw your own deposit early — in most terms, it is forfeited.
If any of those seven cannot be answered from the published terms in five minutes, that is itself the answer.
What we could not verify
We could not find a published regulator dataset showing the distribution of wagering multipliers actually offered in the GB market before and after 19 January 2026, so we cannot quantify how much the cap moved the typical offer. The rule text and its in-force date are documented; the market response is not yet measured in any source we could confirm.
Frequently asked questions
What is the maximum wagering requirement allowed in Great Britain?
Since 19 January 2026, licensees must not apply wagering requirements that require customers to play through bonus funds more than ten times. The cap is measured against bonus funds, not against deposit plus bonus.
Does a 10x wagering requirement mean I only need to stake ten times my deposit?
No. It means bonus funds played through a maximum of ten times. On a £50 bonus that is £500 of total stakes, which is money recycled repeatedly rather than money you must find.
Can a UK casino offer a bonus that combines sports betting and slots?
No. Since 19 January 2026 licensees must not include more than one type of gambling product — betting, casino, bingo and lottery — within a single incentive.
Why do table games count less toward wagering?
Because their house edge is lower, so the operator’s expected revenue per pound staked is smaller. Weighting a game at 10% means only a tenth of each stake counts, which multiplies the effective turnover requirement by ten.
What is the most common reason a bonus is voided?
Exceeding the maximum stake permitted while the bonus is active. It is usually a specific cash figure in the terms, it is enforced automatically, and in most terms it voids both the bonus and any winnings derived from it.
Sources
- UK Gambling Commission — Gambling promotions to be safer and simpler (26 March 2025)
- UK Gambling Commission — Proposal 1: ban or limit the use of wagering requirements
- UK Gambling Commission — Proposal 2: ban mixing of products within incentives
- The Gambling Act 2005 (Operating Licence Conditions) (Amendment) Regulations 2025
- UK Gambling Commission — RTS 14, responsible product design
- UK Gambling Commission — Licence Conditions and Codes of Practice (LCCP)
Related reading: our RTP explainer and slot volatility guide.
Responsible gambling
A bonus is an incentive to stake more than you otherwise would, over a longer period than you otherwise would. That is what it is designed to do, and the arithmetic above does not change it. Set a deposit limit before you claim one, not after.
If gambling is affecting you or someone you know, contact GamCare on 0808 8020 133 (free, 24/7) or visit BeGambleAware.org. UK players can self-exclude across all UKGC-licensed operators via GAMSTOP. You must be 18+ to gamble.
Editorial analysis. 18+. Please gamble responsibly.