This guide is general information about how UK gambling regulation works and is provided for educational purposes only. It is not legal advice. Regulations and figures change over time, so check the UK Gambling Commission and official sources for the current position before relying on any detail. 18+.
How Casino Games Are Tested for Fairness
Before an online casino game can be offered to UK players, it has to be tested to confirm it works fairly and as described. This testing is what sits behind the assurance that licensed games are not fixed, and it involves independent specialists rather than the operators themselves.
Independent test houses
Games and the software behind them are examined by independent testing laboratories – well-known examples include eCOGRA, GLI and iTech Labs. These bodies assess whether a game’s random number generator produces genuinely unpredictable results and whether its return-to-player percentage matches what is claimed.
Testing against UK standards
In Great Britain, games must meet the Gambling Commission’s remote technical standards. Testing checks that a game complies with these rules before it is certified and allowed to go live, and games can be re-tested or audited afterwards to confirm nothing has drifted.
How randomness is verified
Return-to-player figures describe how much a game pays back over a very large number of rounds, not over a single session. Test houses run statistical analysis across millions of simulated rounds to confirm a game’s long-run behaviour matches its design, which is why short-term results can vary so widely.
What certification means for you
A certified game from a licensed operator gives you a reasonable assurance that outcomes are random and the published payout figures are accurate. It does not change the house edge or guarantee winnings, but it does mean the game is behaving honestly. Certification only counts where the operator is licensed in the first place.
Frequently asked questions
Who tests online casino games?
Independent testing laboratories such as eCOGRA, GLI and iTech Labs. They check the random number generator and the return-to-player percentage against the relevant technical standards.
Does testing mean a game pays out more?
No. Testing confirms results are random and the published return-to-player figure is accurate over the long run. It does not remove the house edge or improve your odds in a session.
What is return to player?
It is the share of all stakes a game is designed to pay back over a very large number of rounds. It is a long-run figure, so individual sessions can be far above or below it.
Can a casino secretly change a game's return-to-player?
The return-to-player is set by the game's provider and tested and certified before the game is released. An operator cannot quietly alter a certified game's percentage, and where a game offers more than one configured version the rules require transparency about which is in use. This is part of why independent testing matters: it confirms the figure is accurate and that the version players are using behaves as certified, rather than being changed behind the scenes.
Related guides: Are online casinos rigged? · Slot game design rules · The UK Gambling Commission
18+. Please gamble responsibly. Gambling should be entertainment, not a way to make money, and you should only stake what you can afford to lose. For free, confidential support, contact the National Gambling Helpline on 0808 8020 133 (run by GamCare, free and open 24/7) or visit BeGambleAware.org. If you want to take a break, GAMSTOP lets you self-exclude from UK-licensed online gambling sites free of charge (begambleaware.org · gamstop.co.uk). Fortune Games operates under UK Gambling Commission licence 39175.