Each slot or game we use on casino sites have a theoretical Return to Player (RTP) displayed as a percentage. In the majority of cases, this RTP remains constant across all casino sites. However, certain slot providers have the ability to have their slot’s RTP tweaked by the casino. As matched bettors we are always targeting the maximum value from an offer and so it is important for us to understand how different RTPs affect the Expected Value (EV) of an offer.

One provider that can have the RTP of their slots tweaked by the casino are Play n Go. Some of their most common slots include Book of Dead, Street Magic, Raging Rex and Reactoonz, Recently, a group of casinos have utilised this feature.

If we google ‘Book of Dead’ RTP, we can see it gives a result of 96.21%, which is still accurate for some casino sites. If we have a 50% deposit bonus offer and deposit £100, we can use the casino calculator on Profit Squad to determine the EV of this offer, assuming Book of Dead has an RTP of 96.21% on a casino site with 35x wagering on bonus funds:

casino calculator

In this scenario, the offer has an EV of £27.29. However, several months ago we noticed that this was not the RTP listed on this particular chain of casinos. Instead, they had tweaked the RTP to 94.25%. If we re-run the calculator, we can see that this causes the EV to drop to £23.19. If it hadn’t been lowered enough, we then discovered that the RTP of this slot had been lowered even further to 91.25%, which drops the EV to £14.46:

matched betting casino calculator

This illustrates the importance of considering RTP when proceeding with Advanced Casino Offers. If we use a slot with an RTP of around 91% compared to one with an RTP of around 96%, we would expect to lose around £13 in EV each time we did the above offer.

Unfortunately, it seems that this chain of casinos have tweaked the RTP of some slots to as low as 91%. Additionally, for slots that do not provide the ability to have their RTP altered, they have set as counting as only 50% towards wagering. This means that we have a choice; we can either wager on a slot with low RTP, or we can use a slot with a higher RTP but have to wager the bonus amount x70 instead of x35.

To see which is better, we run the calculator again. This time we use Bonanza, which has an RTP of 96% but only counts 50% towards wagering so we set wagering multiple to 70:

casino rtp calculator

So, if we use a slot with 96% RTP that only counts 50% towards bonus wagering, we can see that the EV reaches £27.01, even with 70x wagering. This is comparable to our first run of the calculator with the difference being our chance of profit and EV/hour are lower than if the wagering was only 35x.


It is important to always check the RTP of the slot you’re playing on, sometimes a google search will bring up inaccurate results. In most cases, the RTP of the slot is displayed within the game menus or on the website. We should then always double check the EV of an offer by using the casino calculator and decide which slot is best to use by running the numbers.


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