A cashback bonus is a type of online casino bonus given to customers in order to reward them for playing at a particular online casino. Cashback bonuses are a great way for players to get some of their money back after losses, or even to just enjoy the casino games without having to risk their own money. Most online casinos offer cashback bonuses in the form of a percentage of the amount that the customer has played during a certain period. The percentage can vary from casino to casino.