The house edge does not mean that you always lose while playing slots. The important thing to understand about slot machine RTP is how averages work. For instance, a 95% slot would have a 5% house edge. The house edge in slots is calculated by simply subtracting the RTP from 100. That’s why this expected loss for the player is also called an online slot house edge. Remember, folks, the number one rule of gambling is that the house always wins. On average, you should be able to walk off with £95.Īs you may have noticed, the RTP in online slots is always below 100%. For instance, let’s say you’re betting £100 on a 95% RTP game. RTP stands for Return to Player and it describes the percentage of the stake that is paid out to the player on average.