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Slots and RTP –  All You Need to Know!

If you have ever read through an online slot machine review or watched an online slot video or stream before, the chances are you have seen the term RTP or Return to Player frequently mentioned throughout the article along with numerous other terms relating to a slots potential, volatility and whether it is a high or low variance slot.

There is an endless list of slot terminology, but RTP is a critical one, very often misunderstood and frankly misused by players and casinos alike.

In recent times players are now faced with potentially many different versions of what appear to be visually identical slots, but they have configurable RTP settings that can be set by the operator (casino), so it’s even more important that you should have an understanding of what RTP is and how it can in the long term affect your overall slot gameplay.

So, What is RTP? How is it calculated?, How does it affect my gameplay? How do I check my own RTP? How do I check the slots I’m playings RTP? are all questions to which you will know the correct answer after reading this article.

Think of RTP as the Inverse of the Casino’s House Edge!

Firstly we need to take a small step back and understand how and where these figures come from.

Before an online slot ever reaches a casino lobby, the slot developer in creating the new machine will have designed the slot to pay back a specific percentage of money wagered over time or “return it to the player” and arrive at a figure which is less than 100%.

For online slots specifically, this current trend is generally in the 94%-97% region for the default slot version. You may get a few outliers but this seems to be the default current target for developers.

The casino always has a house edge, that is just a fact that covers all games that are offered by them, so with this in mind, the slot developers will always make sure that the RTP gives them this house edge.

In terms of online slots, this house edge could be anywhere from 1% up to 10%, so in terms of the RTP, it would be a 99% RTP slot and a 90% RTP Slot in these examples, but as previously noted new releases normally come in at around 96%.

This figure set by the slot developer will take into account all the paytable values, hit frequencies, Max Win Caps, Bonus Frequencies, RNG and all sorts of complex reel strip maths we don’t really need to comprehend.

They have a specific theoretical RTP value in mind during the design process, and all these combinations will be made to produce this outcome. By this I mean they didn’t just design a slot then test it and magically find it was 96% RTP, this value is a key part of the initial design process!

All we really need to be concerned about is that there is a final value for RTP and this value is important to us as a player.

Book of Ra Slot - RTP Value

Check the RTP of a slot before you play!

Players from the UK can easily check the RTP of a specific slot by simply loading up a slot at their chosen casino and checking through either the paytable section or game rules. This does require an account at the casino, as demo play is prohibited with an account for UK players.

The RTP must be listed in either of these sections. This is mandatory for all UKGC licensed casinos serving players from the UK.

Some casino sites will also publish a long list of RTP values for all of their slots, this does allow checking the values before signing up, but you should always check through the paytables and game info before starting to play on any site.

It’s just another player beware check you should be going through at any casino you play to verify you are happy with the version of the slot you are playing.

To give you a real-world example, we will use the Play’n GO slot Diamonds of the Realm as an example. It’s default RTP setting is a very decent 96.23%, but there are numerous other settings casinos can opt to use as follows.

Range of Slot RTP settings

  • 96.23% (Default)
  • 94.26%
  • 91.27%
  • 87.29%
  • 84.27%

Whilst these RTP values may look like minor percentages differences in the settings, over the long term, these small differences in value have a much larger impact on your overall play than you might be aware of.

Play'n GO Theoretical and actual RTP

In the Play’n GO slot example shown above, they have gone one step further. In addition to listing the theoretical RTP of the slot, you are also given the actual slot RTP as it has been performing for all players combined over the last month and the last six months.

If the values presented here are vastly different over a large period of time, it may well be looking into further. Still, factor in there may be incredibly rare massive wins lurking in the machine or things such as a progressive jackpot that hasn’t been won for months that could account for a large proportion of a slots theoretical RTP.

It could also be that enough people aren’t playing the slot, so you have a relatively small sample size compared to the billions of spins that would have been tested to determine its overall RTP figure.

Testing the RTP is valid and correct!

Each slot release has to pass through various strict certifications. This includes tests to prove that the outcomes are random (RNG Tests) and that the theoretical Return to the Player matches what the slot developer claims to be (or very, very close to!).

These reports go into can go into further detail about the breakdown of a slot machine’s RTP, figures such as the percentages of RTP that is awarded from the base gameplay and the individual or special bonus features, a slot may have features like a Progressive Jackpot, and these will definitely have an impact of the calculated RTP and should be freely available in the paytable rules as a percentage of the RTP.

The important term here is the word theoretical as when ran through these scrutinous tests, millions or even billions of spins will have been tested on the machine, so the maximum wins, win caps, or best bonus feature will all have occurred at some point during these billions of spins, and we end up with a value at the end of the tests that matches the same figure as the developer is listing for that release.

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Simple Slot RTP Example

In this example, let’s say our amazing new “Book of Example slot” comes with a fixed 95% RTP value.

This 95% theoretical value means it will return £95 for every £100 wagered when based on a very large number of spins.

Of course, if our Book of Example Slot is a very high variance machine, the actual figures for a player’s individual slot sessions could vary drastically. Their RTP may be much lower or higher if they win a lot during a short session.

So let us remove all variance, volatility, hit frequency, bonus rounds etc., completely from the machine and make this the most uninspiring slot ever created!

Remove all Variance and Volatility

We design our Book of Example slot to make every spin a winning combination that pays back £0.95 credits for every £1 bet.

In the simplest form, we have now created a slot that has a consistent 95% RTP. It isn’t much fun to play, we are never going to win on it, but it is still a 95% RTP slot.

From this stripped-down example, you can hopefully see why variance, volatility and bonus triggers are required to make a slot enjoyable to play!

But let’s continue playing our award-winning Book of Example slot and see what happens to our balance with £1 bets.

  • After 100 spins, we have wagered £100, and the machine has returned £95. We have lost £5 – Balance is £95 (RTP is 95/100*100 = 95%)
  • After 200 spins, we have wagered £200, and the machine has returned £190. We have lost £10 – Balance is £90 (RTP is 190/200*100 = 95%)
  • After 500 spins, we have wagered £500, and the machine has returned £475. We have lost £25 – Balance is £75 (RTP is 470/500*100 = 95%)
  • After 1000 spins, we have wagered £1000, and the machine has returned £950. We have lost £50 – Balance is £50 (RTP is 950/1000*100 = 95%)

Hopefully, with these straightforward examples, you can see the effect of the house edge and how RTP affects your balance. The more money you wager, the more money you lose over time with a fixed RTP value.

Introduce a lower 90% RTP version

If we introduce a new Book of Example slot with the same settings but a lower RTP of 90%, this super-tight version pays back £0.90 on every spin instead. Let’s go through the numbers again and see how it affects our balance and gameplay.

  • After 100 spins, we have wagered £100, and the machine has returned £90. We have lost £10 – Balance is £90 (RTP is 90/100*100 = 90%)
  • After 200 spins, we have wagered £200, and the machine has returned £180. We have lost £20 – Balance is £80 (RTP is 180/200*100 = 90%)
  • After 500 spins, we have wagered £500, and the machine has returned £450. We have lost £50 – Balance is £50 (RTP is 450/500*100 = 90%)
  • After 1000 spins, we have wagered £1000, and the machine has returned £900, we have lost £100 – Balance is £0 (RTP is 900/1000*100 = 90%)

Obviously, no one will ever play our Book of Example slot as it’s impossible to ever win on it.

Still, by removing all forms of variance and volatility and hit frequency from the machine, you can see a lower RTP value’s effect on a slot, thanks to these examples.

The reduction of 5% in RTP meant that our balance had reached zero by the 1000th spin on the 90% RTP machine.

Comparing the figures, the 5% change in RTP results in a 100% increase in the money lost per spin,

After 1000 spins on the 95% machine we had lost £50, on the 90% machine this was £100.

And this is why RTP is important for you as a player, you may not notice it on a short session on a highly volatile machine, but over an extended period of time, it will have a drastic effect on your gameplay!

How do I work out my own RTP?

There are numerous ways in which you can find out your own RTP. Some will require forward planning.

Many good casinos will, if asked, provide you with this information. You could, for instance, contact live support at your casino and request your RTP from them. This could be a session of play, date, month, or even a lifetime value.

This may take time to be reported back to you and is not something you should be constantly concerned about and frequently asking them for.

The alternative is to track this yourself, which can be troublesome if you are constantly changing bet sizes, as you need to keep track of the total money wagered.

It is far easier to track 100 spins at £1 than 100 spins with bet sizes from £0.50 to £5 that you alter on every spin, but by recording how many spins and the bet size, you can work out how much money in total you have wagered.

Your starting balance and current balance will enable you to see if you have won or lost money. From this difference in this value, we can also quickly work out what our session RTP was.

A quick, simple example.

You deposit £100 at a casino, load up your favourite slot and play 500 spins at £1 stake on this machine. Your end balance after these 500 spins is £50.

So from this information, we can see that you have wagered in total £500 (500 spins at £1) and lost a total of £50 (£100 – £50).

Because we kept the example simple, we know that we have had £450 returned to us  (£500 Money Wagered – £50 Difference from starting balance).

With this information and a quick bit of maths, we can work out our session RTP using the amount of money returned to us, divided by the total money wagered and then multiplied by 100 to give up a percentage value.

In this example, 450/500  *100 = 90%

What if I continue playing and improve my RTP?

This statement is actually as dangerous as someone who knowingly chases their losses, Never continue to play to “improve your RTP”, and we will explain why.

So in the previous example, we ended our session with a 90% RTP, not ideal, but we had a good amount of playtime.

The slot we were playing has a listed RTP value of 95% RTP so surely if we play longer, we can improve our RTP and reach this value?

This statement is true, and over an extended play, you will edge closer to this figure, but let’s look at the money concerned and see what actually happens whilst reaching this figure.

We do a further 1500 spins at £1 before going bust. We decide to work out our complete session RTP, which includes the first 500 spins from the previous example.

That’s 2000 spins in total, £100 lost in total, so in reaching this figure, we have had £1900 returned to us in the process of doing these 2000 spins. Doing the calculations again, we can see,

Extend play session 1900/2000*100 = 95%

So as you can see, we “improved” our RTP to the stated figure for this machine, but in the process of wagering more money, we actually lost more money in the process of doing so, which is a futile goal for anyone to attain.

So what is knowing the RTP actually good for?

In reality, knowing the theoretical RTP of a slot is an excellent indication for making an informed choice about whether or not you decide to play a slot.

Be aware that slots may visually look identical but can come with different RTP settings is key. You can now manually check a machine and make an informed choice about whether you decide to play at a certain casino or not.

Knowing this information,  it makes sense to seek out casinos that offer the highest RTP versions whenever possible.

If 2 banks had 2 hugely different savings interest rates and offered the same service, then I would be opting for the highest interest rate, and the same logic applies here.

Constantly working out your own RTP is quite a futile thing to do. If the value is lower than 100%, it simply means you have lost money. If it exceeds 100%, then congratulations, you have won money.

It tends only to be those horrific slots sessions where you bust quickly that sees you working out your RTP in frustration to what was a bad slot session, as some form a justification to how bad it was because you have a figure that confirms that was the case.

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