Can Casinos Adjust Online Slot Machine Payouts?
If you have played or thought about playing online slots, you may have wondered how the payouts are decided. With so many games, features and possible prize amounts, it can be unclear who sets these figures and whether casinos can change them.
This guide explains how payouts are set for UK online slots, how different versions of the same game can exist, and the safeguards in place to keep the process fair. It also covers the difference between payout percentages and volatility, why games might seem to pay differently over time, and how you can find payout potential details before you play.
How Do Online Slot Payouts Actually Work?
In the UK, online slots use a piece of software called a Random Number Generator (RNG). This is a computer programme that produces thousands of number sequences every second. When you press “spin”, the game instantly uses one of those sequences to decide the outcome. It works in the same way whether you are spinning for £0.10 or £2.
The RNG ensures each spin is independent. The outcome does not take into account any previous results, so there is no way to predict what will happen next. In the UK, RNG systems must be tested and approved by accredited independent laboratories before the game can be offered to players.
You should also see a Return to Player (RTP) percentage in a slot’s game information. This is a theoretical figure set by the developer to show how much the game is expected to return over a very large number of spins. For example, an RTP of 96% means that, in theory, £96 could be returned for every £100 staked over millions of spins. This is not a prediction for a single session and does not guarantee any winnings.
Can Casinos Change Slot Machine Payouts?
Casinos in the UK do not write or alter the software for slot games. The games are made by specialist developers who decide the game’s design, features, and payout potential settings. For certain slots, the developer may create several versions with different RTPs, such as 96%, 94% or 92%.
When an online casino adds a slot game to its collection, it can choose from the versions provided by the game’s developer. Once that chosen version is live, the casino cannot change the payout percentage (RTP) itself. If the RTP is to be changed, this must be done by the game developer, and the updated version must go through independent testing and regulatory approval before it can be made available to players.
Are Online Slot Payouts Regulated?
Online slot payouts in the UK are regulated by the UK Gambling Commission (UKGC). This means both the RNG and the RTP are checked to ensure they work as intended. Independent testing agencies verify the software before the game is released, and ongoing monitoring helps ensure the actual performance stays in line with the stated RTP.
If a game is found to perform outside of its approved parameters, it must be removed from play until the issue is resolved. Only UK-licensed casinos can legally offer these approved games to players in the UK.
Do Payouts Vary Between Casino Sites?
The same slot game can have different RTP versions available. If the developer has released multiple versions, one casino may choose the higher RTP setting, while another may select a lower one. This is why you might notice a game showing a 96% RTP on one site, but 94% on another.
These figures must be made clear in the game’s information section, so you can check them before you play. While a higher RTP version theoretically means a better average return over many spins, the results on any given session will still be random, thanks to the RNG.
Slot Machine RTP vs Volatility: What’s the Difference?
Slots are random, and neither the RTP nor the volatility can guarantee that you will win. The RTP simply shows the theoretical long-term average return calculated over millions of spins, not what any one player will receive. Volatility describes the general way a slot may award wins:
- Low volatility – potential wins are usually more frequent, but smaller in value.
- High volatility – wins are usually less frequent, but may be larger if they occur.
For example, a low volatility slot might give smaller wins every few spins, while a high volatility slot might go longer without a win, but award a bigger prize if it does.
Because every spin is independent and completely random, two people playing the same slot could have very different experiences.
Why Your Slot Game May Feel “Tighter” Over Time
Sometimes you might feel a slot was “paying well” at the start, but has since slowed down. This is simply due to natural variation. Because each spin is random, you may potentially experience a series of wins, a series of losses, or a mix of both in any order.
The RTP is calculated over millions of spins, not the amount of time you may be playing. So, even if a slot game feels different from one session to the next, the underlying operation remains the same.
How to Check Slot RTP Before You Play
Before starting, you can look for the RTP in the game’s help, menu, or information section—often marked with an “i” symbol. Some casinos might also list RTPs in their game lobby or in a help area on their site. If you cannot find it on the casino site, the developer’s official website may provide the figure.
Because some games are available in multiple RTP versions, checking the figure on the site where you are playing can help you better understand the version you are playing.
Play Slots Online at O’Reels Casino
At O’Reels, you can explore a wide selection of slot games from well-known developers, all offered under a UKGC licence. This ensures that every slot available on O’Reels meets strict UK standards for fairness, with results determined by independently tested RNG software.
Each slot on O’Reels displays its RTP percentage in the game’s information section, making it straightforward to see how the game is set up and compare different options. You will also find a variety of themes, features, and volatility levels, giving you the flexibility to choose the style of play you prefer.
You can log in or join O’Reels to explore the full game library, see detailed information for each slot, and try new releases, alongside well-known favourites.
If you start to feel less enjoyment from playing, or are concerned about the time or money you are spending, it may help to take a break. You can also use deposit, time, and loss limit tools to help manage your play in a way that works for you. Please play responsibly.
*All values (Bet Levels, Maximum Wins etc.) mentioned in relation to these slot games are subject to change at any time. Game features mentioned may not be available in some jurisdictions.
**The information provided in this blog is intended for educational purposes and should not be construed as betting advice or a guarantee of success. Always gamble responsibly.