RTP, RTP or RTP all describe the same thing: the percentage of wagers returned to players over a given period of time. The information can be given for each individual casino game as a theoretical average or for the entire casino as the actual payout percentage. Good online casinos usually offer high payout rates beyond the 90% mark. Variance is another important issue as it affects the frequency and size of wins. In order to play profitably it is advisable to look for games with high RTP.