All top cashback casinos will have different bonuses which range from it as part of a welcome bonus or ongoing promos for loyal players. You will get your cash back after you have used your own money. Different bonuses will depend on which type of bonus it is, but once you join a casino offering cashback it is important to read the terms and conditions. If it is part of a welcome bonus, you will get your cashback as soon as your losses are calculated according to cashback terms. If it is part of daily or weekly cashbacks, you will get it after that pre-specified period.