Over the course of putting together the Slotjunkies network, I made it one of my challenges to get hold of the RTP (long term expected 'return to player' percentages) for as many games as possible. You see most games here now have that info.
The figures for Microgaming slots and Playtech's games along with those from WMS and Aristocrat are direct from the spec sheets in most cases so are pretty much spot on. Those from the other providers have mostly come from a casino source and should be regarded as a ballpark although even in these instances, the RTP shown is likely to be accurate for many games.
Gathering The RTP Data
The first challenge was to discover which manufacturers issued their slots with a single RTP and which used multiple RTP's for different casinos. Where the latter method was employed, the manufacturer is usually able to supply a 'range' - in fact each slot has to have a fixed (and reasonable!) RTP range to meet the criteria of licensing the games. The vast majority of online slots by the manufacturers listed below have an RTP of around 95% (+/- 3%).
Ultimately I was able to get fairly accurate figures for IGT, Novomatic, WMS, Playtech and a good number of Microgaming slots but just a very loose indicator for RTG ('Realtime Gaming') games. However, I don't really consider the latter particularly important as they have a relatively specific audience which in time I expect will diminish. Suffice to say, most of them are around 95% at the RTG-powered casinos here at Slotjunkies anyway.
The upshot of that is that the RTP information you see here, be it an exact figure or a range, is likely to be pretty accurate to within 0.1%. I don't guarantee that of course - it's not under my control - but working in the player's favour is that all the manufacturers of games listed here are required to submit their games, along with the RTP info, for certification and if they change the RTP, the games have to go back through that loop.
Finally, please note that the RTP is an 'expected' return based on millions of spins. You will rarely if ever get the same RTP as published unless you are spinning millions of times!
January 2021
From time to time I double check some numbers or approach the contacts in the industry from the operations an manufacturing side who have kindly helped me build this list and I like to think that this information will remain accurate for as long as I run the Slotjunkies site and network.
Re-Publishing The RTPs
If you decide to use the RTP information and publish it on another website, all I ask is that you clearly link to this page to show readers how and when the RTP information is gathered so that they can be sure what they are reading isn't just 'best-guesswork' as I have had players suggest before now!
Simmo! (contact)

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