Bonus Abuse Rules UK: What Gets Your Winnings Voided

What "bonus abuse" means when a casino writes it down

There is no real significance to the text in Britain. Scroll through each of the 133 clauses in the Gambling Commission’s Licence Conditions and Codes of Practice, and you will find no mention of bonus abuse, advantage play, arbitrage, or irregular play. Operators publish this text in the agreements, and therefore, it is defined differently for each.

There are three distinct behaviours that all end up in the same bucket.

• Dishonesty. Opening several accounts, using someone else's card, running bots, colluding with other players. Nobody seriously argues these should be allowed, and every operator on this list bans them.
• Taking the risk out. Arbitrage, hedging, covering every outcome so a profit is locked in whatever happens. The casino is offering a gamble, and this removes the gamble from it.
• Playing the terms. Moving from a game that contributes ten per cent of your wager to one that contributes the full amount once a big win lands, or cutting the stake right down once you are ahead. This is reading the small print and acting on it.

Only the first can be considered cheating. The third is behaviour that the terms of the agreement suggest is encouraged, since a published document outlining the game weightings or defining stake caps is outlining the boundaries of optimal play. It is in that gap that the discussions start, and it is why the Competition and Markets Authority took two and a half years to review this issue.

The most concise definition on this list is Midnite’s. According to its general promotion terms, Midnite calls three things “Bonus Abuse:” “the majority of your transactions involve bonus funds,” “strategies that ensure profit regardless of outcome,” and “taking advantage of promotions to engage in arbitrage betting.” Read the first one again. A player that only deposits when a promotion is available meets the definition from a pure language perspective.

What each of the ten actually calls bonus abuse

These are the operators’ own words, taken from the British published terms in August 2026. The interesting thing is not that they all ban abuse. It is how different they are in their definitions and how many of them are silent on the issue.

Three sites do not publish anything that we have access to. That says nothing about the law. It says what we could read, because a terms page that will not load from outside Great Britain is a common issue in this case.

Note which documents you are reading. Several of these brands operate separate, market-specific terms through different companies. Bet365’s UK Casino Terms are issued by Hillside (UK Gaming) ENC through Gambling Commission account 55149, and its international version is a separate contract with Bet365 with different terms and conditions. If a bonus rule you found on the internet uses Euros or refers to a regulator other than the Gambling Commission, that is not the contract under which your British account is located. Our licence check page describes how to quickly verify this.

Your winnings are a debt, and that is newer than you think

For over two centuries, a bet was not a contract that could be enforced. Section 18 of the Gaming Act 1845 declared gaming contracts void, meaning a bookmaker could not be sued for refusing to pay. This section was completely removed by the Gambling Act 2005, and was replaced by section 334. Section 335 made the following change: “The fact that a contract is a gambling contract shall not affect its enforcement.” Both sections were effective from 1 September 2007.

This sentence is the basis of the subsequent paragraphs. A bonus offer is a part of the contract. A winning bet that is settled is a debt. A clause which states that one party has the right to make a determination after the fact as to whether a debt is owed is a clause that a court has the right to review.

The CMA articulated this viewpoint when it addressed the industry in August 2018. One of its slides on play restrictions articulates this principle by saying “winnings constitute an enforceable debt” and explains that “terms seeking to legally reserve an operator’s liability are imbalanced.”

The rules four gambling firms agreed to in 2018

The CMA commenced its investigation into online gambling on 21 October 2016, pursuant to the referrals made by the Gambling Commission. On 23 June 2017 it announced enforcement action and identified three areas for concern. The focus of this page is on the third concern.

“Potentially unfair rules that restrict certain play strategies, on which firms rely to deny customers a pay-out when they come to claim their winnings” is how one regulator described the practice, and then promptly addressed the issue.

Ladbrokes, William Hill and PT Entertainment provided formal undertakings on 1 February 2018. BGO Entertainment gave its undertakings on 23 March 2018. The four documents are identical word for word on the three paragraphs dealing with play restrictions, and those paragraphs should be read in full.

• Paragraph 7, no open-ended discretion. Terms setting out promotional play restrictions must "clearly specify all prohibited types or patterns of play, and do not reserve sole discretion" on the operator to decide when play falls inside those categories, or to decide that some other form of play is a breach.
• Paragraph 8, keep cheating in its own clause. Terms about account fraud, collusion, multiple accounts, software manipulation, exploiting loopholes and "other behaviour which amounts to deliberate cheating" must sit in separate terms from the promotional play restrictions.
• Paragraph 9, you get told which clause. Where a customer is to lose winnings or be refused a withdrawal for breaching a promotional play restriction, they must be "provided with a full explanation of the breach of the relevant Promotional Play Restriction, including the specific terms breached".

The CMA's own summary of what had been going wrong is direct. Operators began “deeming certain play strategies invalid / ‘abusive’ after the event”. Terms and conditions were “opaque and nebulous”, “conferring excessive discretion”. Sanctions were “disproportionate”, with “nothing to stop consumers from breaching the restrictions”. That point is crucial: software can simply refuse to accept the stake if a stake pattern is prohibited.

The CMA was direct in providing guidance to operators, who only received one sentence: “should set out as comprehensively as possible the play strategies that could lead a consumer to find themselves in breach”, and “should not prohibit a form of play that was not clearly articulated to the consumer in advance”.

These actions are not fully behind us. The CMA described the four undertakings as benchmarks, and noted that the Gambling Commission had made clear its expectations towards the other activities in the market. One of the four signatories, WHG (International) Limited, is the company that owns Gambling Commission account 39225 and runs William Hill for players in Great Britain today.

Three licence conditions sit behind every bonus term

The undertakings bind four companies, and the licence binds all of them. Three separate conditions apply to the wording of a bonus offer. The first of the three also carries the 10x wagering ceiling and the ban on mixing product types. This is covered on our UK casino bonus rules page.

• Social responsibility code 5.1.1, rewards and bonuses. Licensees must "set out terms and conditions, in relation to an incentive, which are clear, transparent, and fair and readily accessible to any customer or potential customer to whom it is offered". That is the condition the January 2026 wagering cap was written into.
• Social responsibility code 4.1.1, fair terms. One sentence long, and it puts the burden in an interesting place. "Licensees must be able to provide evidence to the Commission, if required, showing how they satisfied themselves that their terms are not unfair."
• Social responsibility code 7.1.1, fair and transparent terms and practices. Terms must not be unfair "within the meaning of the Consumer Rights Act 2015", must be transparent within the same Act, and the licensee "must not commit any unfair commercial practices within the meaning of the Digital Markets, Competition and Consumers Act 2024".

The Consumer Rights Act places particular emphasis on section 62. An unfair term states that, “contrary to the requirement of good faith, it causes a significant imbalance in the parties' rights and obligations under the contract to the detriment of the consumer,” and “is not binding on the consumer.”

What this page aims to achieve: no court ruling has been provided where any of the wording is concerned. This page indicates no named operator’s term is unlawful. The issue is more direct and significant. The test is in place. The operator is obligated to defend its actions with the regulator, and you have the right to ask which clause your play is supposed to have breached.

What a bonus abuse investigation does to your account

Suspension comes first, questions after. Three of the larger sites use almost the same phrasing. bet365, William Hill, and Grosvenor all state that the account is suspended, no notification is given, and stays suspended while the actor is under investigation. You must agree to cooperate fully, and funds remain inaccessible and cannot be withdrawn.

None of these sites state a set time for completing the investigation. bet365 and Grosvenor state that they will make “reasonable efforts” to complete the investigation “in a reasonable time”. bet365 also states that if there are delays on the actor’s part in answering, this will affect how quickly the investigation can be completed. This is the only time a schedule is stated at any of the sites we reviewed.

The wording is similar but the implications are different. bet365 said it will “permanently close your Account” after its investigation decides that you engaged in a prohibited activity acting “reasonably”. Grosvenor says it will “restrict or permanently close your Account”. William Hill says it will “restrict, suspend or permanently close your Account”. Except for the William Hill example, the other two examples do not give any example to justify the course of action.

Findings can also reach other operators. William Hill says other operators in its corporate group can restrict, suspend or close your account, and you can do the same to them based on the findings. Grosvenor Group employs the same rule for all its brands which include Bella Casino, Grosvenor, Mecca Bingo, Mecca Games, Kitty Bingo, Lucky Pants Bingo, Lucky VIP, Magical Vegas, Regal Wins and Rialto Casino. They also say that your data can be shared with other regulatory agencies.

A prohibited activities list is not a list of bad behaviours. bet365 has 27 items and the first example is “if you become bankrupt”. Item (d) is “if you repeatedly exceed our daily Account login limit”. Neither of these examples is relevant to bonuses, and neither examples are related to illegal activity. An operator corporate group lumping everything from insolvency to hacking under the same heading and the same result will erode the heading’s value for determining the severity of the prohibited activity.

What a bonus abuse finding cannot take from you

The phrase that is likely the most useful in every document is attributed to. bet365 states, "...will retain the right to withhold all/part of the balance and recover deposits, pay-outs, offers and winnings..." William Hill similarly states, "will recover deposits, pay-outs, bonuses and winnings..". In the same vein, Grosvenor states, "attributable to the Prohibited Conduct".

Of the major operators in the market, all three explicitly link the sanction to the money that left the system due to the activity they have uncovered. Money with no relation to the sanction is out of scope. The only major exception that bet365 states in the clear is where the customer has engaged in illegal activity bet365 "is under no obligation to refund to you any money that may be in your Account".

The additional 2018 obligations specify three further constraints which a promotional dispute should not include.

• Your own deposit. Paragraph 4 requires the deposit balance to be withdrawable at any time, "including when a Bonus is pending or active on the account", subject only to regulatory obligations and a reasonable processing fee.
• Your own play. Paragraph 6 requires that promotional play restrictions and wagering requirements do not apply to play with the deposit balance, except where the software automatically stops you placing a wager that would break them.
• Your face. Paragraph 13 stops operators relying on any term that obliges a customer to take part in publicity, which was a genuine practice: the CMA had found terms requiring players to pose with a winner's cheque before a withdrawal was released.

Two of the ten place the other large 2018 commitment in their own words, regarding not moving the goalposts after you have opted in. bet365 explains that if it withdraws, amends or cancels an offer, “any Bonuses or Offers that you have opted in for or otherwise accrued will still be valid in accordance with and subject to the relevant Offer Terms that applied at the time of their offer”. Grosvenor says the same and adds that, other than in exceptional circumstances, it will give notice. MrQ puts it in a line: “We reserve the right to cancel offers without notice. Any such cancellation will not affect bonuses/free spins already claimed.”

MrQ's fair use policy is the one document here still containing the phrase against which the 2018 undertakings were drafted. As to non-compliance “will be determined by Us in Our sole opinion”. It is fair to say that, of the four named patterns, all are collusion, multi-accounting or depositing with no intention of playing, and MrQ attaches no wagering requirement to any offer, leaving little promotional play to restrict. The policy is version 1, last updated 24 September 2019.

If you are accused, ask for the clause

The most pragmatic thing in this instance is paragraph 9 in the undertakings. When a customer is directed to forfeit winnings or a withdrawal is refused due to the customer breaking T&Cs for promotional play, the customer must be notified of the breach, including the specific sections that were breached. The only exception an operator can claim is when releasing information would create a breach of their other regulatory obligations, which in effect is the money laundering reporting obligation.

• Ask in writing which term and which play. "Bonus abuse" on its own is a conclusion, and the benchmark those four firms accepted asks for the clause and the conduct behind it.
• Keep the offer terms as they stood when you opted in. Two of the ten say in their own contracts that those are the terms that apply, so a screenshot taken at sign-up is worth more later than the live page.
• Work out which regime you are actually in. A held payout is very often an identity or source of funds check, and that runs on completely different rules with a completely different timetable.
• Then use the formal route. Every licensee must offer free alternative dispute resolution once its internal process is exhausted or eight weeks have passed, and the adjudicator will want the clause and your account history.

As the last two points are longer, they have their own specific sections. What a verification hold is and how long an operator can legally place one is set out on casino account verification, and the different routes for filing complaints against specific operators, including which of the ten uses which Alternate Dispute Resolution (ADR) body, is on our casino complaints page.

Think how it probably ends. An adjudicator will interpret and enforce the language as it is written, so they will probably uphold a restriction of this nature. This is the reason it is important to read the crucial terms and conditions before agreeing to offers, and it is also the reason to prefer an operator whose descriptions are more specific. The offers themselves and the value that the wagering requirements eroded are compared page by page across this site.

And if the reason any of this matters to you is that the game is less fun, the operator’s own tools and the free national services are available on our responsible gambling page. Scoring for each site is explained in our review methodology.

Frequently asked questions

What counts as bonus abuse at a UK casino?

There is no definitive answer because no law and no licence term defines it. A search of all 133 terms of the Gambling Commission’s Licensing Conditions and Codes of Practice results in zero relating to bonus abuse, advantage play or arbitrage. Each operator has its own version of this. Midnite lists three types: the majority of transactions made using bonus funds, methods of assurance to guarantee a profit, and offers for arbitrage betting. bet365 has 27 listed as prohibited, and William Hill has 18.

Is arbitrage betting against the law in Britain?

No. Locking a profit by backing all outcomes breaks no law and no licence term says anything about this. What does prohibit it is the contract you signed. bet365’s British terms describe a strategy that takes advantage of differences between prices offered by several Bookmakers to guarantee a profit, and card switching, and define these as prohibited activities. Midnite and William Hill have similar prohibited term definitions.

Can a casino keep my deposit if it says I abused a bonus?

The player limits set by bet365, William Hill and Grosvenor all specify that only money staked is recoverable. Thus, it can be said that on the language used, these terms do not reach money unconnected to the staking. The 2018 undertakings provided to the Competition and Markets Authority, also stipulate that the deposit balance must remain withdrawable at any time including while a bonus is active. A finding of illegal activity is treated much more broadly; bet365 states it will not refund money held in such circumstances.

Can a casino close my account without telling me why?

The three largest sites state that they can suspend an account from the bettors, while they investigate and all do so without notice. The 2018 undertakings also set the standard. In those circumstances, a customer loses winnings or is refused a withdrawal for breaching promotional play restrictions, the customer must be given a full explanation of that breach, and the specific terms that were breached. Write to request this explanation, and if you do not receive any reference to specific terms, take this up via the complaints process.

Does a bonus abuse finding follow me to other casinos?

It can act across a group. William Hill's terms allow it to inform other group companies, and for those companies to restrict, suspend or close any account you hold with them, with the reverse also true. Grosvenor's one-account rule is across the Rank group, which includes Mecca Bingo, Lucky Pants Bingo and Magical Vegas. They also state that your details may be provided to the regulator and other relevant third parties.