Return to Player (RTP) & House Edge Explained

Have you ever heard the saying, “the house always wins”? When it comes to gambling at UK casino sites, players win largely thanks to luck, but the casino wins because the odds are largely in its favour, and although return to player rates (RTP) of up to 98% may sound lucrative the odds are massively stacked against the player. Even on the easiest casino games, the casino is more likely to win, and this is called the ‘house edge’. It is no question that the casino will win in the long run, and it is the house edge that tells us roughly how much the casino wins on average.

The casino does not have to beat every one of its players every time to make a profit, but with Roulette, for example, the casino’s wins are an average of 5.26% in the year. That might sound strange to infrequent players as 5.26% is a small fraction, however, the house edge is based on the amount of the bet, not the amount of money that the player has taken to the casino.

Let’s Begin with Casino House Edge

To put it simply, the percentage is the amount of the player’s bet that the casino keeps as a profit. For example, if you play Roulette with £100, you will undoubtedly lose a lot of rounds, but you will also win several rounds, and after hours of play you will have to bet more than just the £100 because you will have played with your winnings. After several hours you could have gambled £2000, and five per cent of that is £100, exactly what you went in with.

Casino House Edge & The Grind Algorithm

the grind algorithm
The Grind Algorithm

The house edge is fundamentally tied into terminology known as the grind, which is when the casino whittles away your money as you keep re-betting. You can lower the grind by playing games that have a lower house edge, making your money last longer, and you can also heighten the grind by playing games that have a higher house edge. It might seem like there isn’t much point in that, but games with a higher house edge often offer higher payouts.

Though the house edge is important, it is imperative not to look at the house edge as the be-all and end-all system to winning and calculating your average loss. There are several other factors that work in conjunction with the house edge, such as the average size of the bets and the rate at which you play. The quicker you play, the more you will be bled dry. Slot machines have a high house edge, meaning that they are some of the riskiest games to play at a casino, but they are much smaller stakes and there is a chance of winning a jackpot, unlike Blackjack or Roulette.

Most games have the same average house edge at every table, but some games have variable house edges due to the conditions of the game, such as Baccarat having a variable house edge of between 1% and 15%. It is useful to know about the house edge so that players can understand which casino games give the best payouts on their bets.

Improving Your Odds

Casinos will always have the house edge, but before you despair – and quit before you’ve even started – rest assured that there are still steps that you can take to improve your chances of that desired win. You can give it your best possible shot while playing online slots by preparing wisely. Choose a game with a high RTP (Return to Player) value or better odds, for instance, and ensure that you know your game before you play. This should involve studying the slot game rules and playing a free demo for practice before you risk real cash wagers. Furthermore, plan your budget and stick to the amount that you can comfortably afford to gamble. Take your time, and enjoy the game – if you didn’t succeed this time, at least you had fun!

The House Edge: Facts & Figures

  • Slot games usually have a house edge anywhere between 2 and 20%.
  • A slot game that has a house advantage of at least 8% is often referred to as ‘tight’.
  • If the slot game has a house edge of less than 4%, it can be referred to as ‘loose’.
  • The house edge in American Roulette is 5.26%, as opposed to 2.70% in European Roulette.
  • Most table games have a house advantage of at least 5%.

RTP – Return to Player Rate Explained

The Return to Player (RTP) is a figure that you should always be aware of when playing online slots. This tells you the average payment that will be made to a player of the slot.

For example, a game that has a 95% RTP means that on average, it will pay out £95 for every £100 that you play on that particular slot. The keyword here is ‘average.’ That figure of £95 won’t be the amount that is returned on each and every £100 staked, but it will be the average.

Checking that figure is correct isn’t the easiest task unless you are very good at keeping records. That figure is based on all the bets that players have made on a game, not just one particular player. It’s also worked out on as many as 100,000 spins and that is a lot to count!

If the RTP for the slot you are playing is 95%, you may well have times when your RTP is higher than that figure and other times when it is lower. That ties in with the unpredictability of slot machines games.

A further complication is that sometimes to achieve the stated RTP you may have to be playing at the maximum bet. Some slots offer players the chance to play a set number of spins where the RTP will be higher than normal, even with guaranteed wins for each of those spins. This will come at a cost though and a certain payment will have to be made to activate that feature. Again, it is important you keep an eye on your budget.

High RTP = Low House Edge

The higher the RTP, the lower the house edge. One of the advantages of playing online is that online slots generally have a higher RTP than those you will be playing down at your local slots haunt. Some of those can see the RTP down to 85%.

There is no law in place in the UK that sets a minimum RTP. If it were too low though it’d be unlikely players would be queuing up to play. The majority of online slots that you will play will have an RTP of between 94 and 96%. If they creep above that figure, then that is a high payout slot. Those games that do have a lower RTP, perhaps below 90% tend to be ones that have progressive jackpots. These can be six-figure sums but are very difficult to win.

Making the RTP of games known is important. Online casinos that hold UK Gambling Commission licenses (and want to keep them) have to make the RTP easily accessible. The more transparent that gaming can be, the better. Reading reviews of online slot games is always helpful and the RTP usually forms part of the information provided.

If the designer of the game were to give inaccurate figures, they could find themselves in hot water with Gambling Commissions. People will find it hard to trust them and in this highly competitive industry, trust is a very valuable commodity. See our ultimate guide to online slots for more juicy info.

Which Slots Have The Highest RTP?



5 Reel Drive96.95%
Big Top96.94%
Immortal Romance96.86%
Thunderstruck II96.65%
Age of Discovery96.62%
Arctic Fortune96.58%
108 Heroes96.56%

Other UK Slots With High RTP

When you play an online slot, it is important to look at the Return to Player (RTP) that the game has. For example, if the RTP was 95%, then this suggests that for every £100 wagered, you would get £95 back. It’s only an average so it can be higher and lower.

The trend seems to be that the games that offer very high RTPs do so at a cost. When playing the base game, the RTP is good but to get up to one of as high as 99%, an increased stake or betting at the maximum level is required. Let’s look at UK Slots that have the highest RTPs.

Goblin’s Cave (99.32% RTP)

The RTP with this game is 99.32%, so just a 0.68% house edge or is there? Reading the rules of a UK online slot is important. Doing so with this game will inform you that the 99.32% RTP only comes into play when betting at the maximum amount. As with other games on this list, you need to make a decision between staying at the regular RTP or spending a bit more to get the higher one.

Ugga Bugga (99% RTP)

This is another online slot that has an RTP of over 99%. Only just though as it’s 99.07% and the jackpot here is 1000x the bet that has been placed on that spin. The RTP sounds good but this is a low variance game. That means the wins that do come along tend to be of the lower variety. They do keep your account balance ticking over though.

Ocean Princess (99.7% RTP)

The RTP here is also 99.07% but again you have to be playing at the maximum bet for you to receive that figure. This mermaid themed game only has three reels compared to the five that most UK online slots have these days. High rollers can win as much as 1000x their stake if getting three Crown Wilds on an activated pay line.

Ooh Aah Dracula (up to 99% return to player)

This vampire has many online slots dedicated to him. Thankfully, they can be played during the day as well as the night. Its RTP is 96% for the base game but rises to 99% if you enable the Big Bet Mode.  Do be careful with your budget though as the spins with the higher RTP can cost as much as 30x your stake (not a word to mention when Dracula is around) but could get you into the lucrative Graveyard Bonus.

Jackpot 6000 (98.9% return to player)

The RTP here is just under the 99% mark at 98.9%. It’s another three-reel game, perhaps slot designers feel that they have to offer a higher RTP to attract players to them. If you want the higher RTP, again you need to be betting at the maximum level.

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