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Explainer
What the licence actually makes them do
“Licensed and regulated” appears in every casino footer in the country. It is worth knowing what the phrase buys you, because the answer is more specific and rather more interesting than most people expect.
The licence, and who issues it
Gambling in Great Britain is governed by the Gambling Act 2005, which created the Gambling Commission and made it an offence to provide facilities for gambling without a licence. A business that wants to offer casino games over the internet to people in Britain needs a remote casino operating licence. Every operator we cover holds one, and each licence carries an account number and a licence number that appear on the Commission’s public register.
The register is worth understanding as a document. It lists the legal company holding the licence, which is frequently not the brand you see; the specific activities that company may offer remotely, such as casino, bingo or betting; the date each of those activities was first authorised; the web domains the company has declared; and whether the whole thing is currently active. It is free to search and it is the only operator-specific source we treat as authoritative.
Random number generators, and who checks them
Casino games are driven by a random number generator. An RNG on its own proves nothing — anyone can write software that claims to be random. What matters is that somebody independent has looked at it.
Under the Commission’s remote gambling and software technical standards, games and RNGs must be tested by an approved test house before they are released for play, and the results must be submitted to the Commission through its games register. Test houses are not chosen freely: the Commission maintains a published list of approved houses, and they must hold accreditation to BS EN ISO/IEC 17025, the international standard for testing and calibration laboratories.
The testing itself is more than a statistical spot check. It includes reviewing the RNG’s documentation and source code to confirm the implementation matches what is claimed, researching the algorithm for known weaknesses, and statistical testing of the raw output as well as of scaled and shuffled results. Licensees who develop or procure games must also commission an annual games testing audit from an approved test house.
You cannot play until you have been verified
Since 7 May 2019, operators must obtain and verify a customer’s name, address and date of birth before that customer is allowed to deposit or gamble. There is no grace period; the previous rule, which gave operators seventy-two hours to complete checks, was withdrawn precisely because it let people gamble before anyone had established who they were.
The requirement goes further than real-money play. Age verification must also be completed before a customer can access free-to-play versions of gambling games on a licensee’s site. Simply typing a date of birth into a box is not sufficient — the Commission has been explicit that self-declaration does not meet the standard.
The rules that changed how slots behave
On 31 October 2021 a package of design rules took effect that altered online slots substantially. If you played before that date and have come back since, this is why the games feel different.
- Autoplay is banned. You must physically start every game cycle. Holding a button down does not count.
- A game cycle must last at least 2.5 seconds. This mirrors the minimum already applied to category B3 gaming machines.
- Features that speed up play are banned, including turbo and slam-stop mechanics, along with anything giving the illusion of control over the outcome.
- Losses disguised as wins are banned. A game may not use celebratory sounds or imagery when the return is equal to or below the stake.
- Playing multiple slots simultaneously is banned, so no split-screen or multi-screen arrangements.
- Your position must be visible. Operators must clearly display total losses or wins and time played during a slots session.
The same package permanently banned reverse withdrawals across all online gambling, not just slots. Once you request a withdrawal you can no longer cancel it and re-gamble the money, which had been a reliably effective way of losing funds you had already decided to take out.
There is a cap on what you can stake per spin
Maximum stake limits for online slots were introduced by statutory instrument in 2025. The £5 per game cycle limit for adults aged 25 and over went live on 9 April 2025, and a lower £2 limit for adults aged 18 to 24 followed on 21 May 2025 after a six-week transitional period.
One detail is routinely misreported: the caps apply to online slots only. They do not apply to other casino games such as roulette or blackjack, and they do not apply to betting.
Self-exclusion works across the whole market
Since 31 March 2020 it has been a condition of holding a licence that every online operator participates in GAMSTOP, the national multi-operator self-exclusion scheme. One registration blocks you from every online gambling business licensed in Great Britain rather than requiring you to exclude yourself site by site, and it covers operators that launch after you register. The requirement was extended on 1 April 2024 to businesses taking bets by telephone and email.
What none of this does
It does not make the games favourable to you. Every casino game is designed so that the operator retains a percentage of everything staked over time, and independent testing confirms that the game behaves as its published mathematics say — not that the mathematics are in your favour. They are not, and they are not meant to be.
A licence tells you that a business has been vetted, is subject to conditions, must protect your funds and your data in defined ways, must let you exclude yourself, and can be sanctioned if it fails. That is genuinely worth having, and it is the entire reason we build this site around the register. It is not a suggestion that you will come out ahead.
