Cashback Bonus
Cashback is a bonus where the casino returns a percentage of your net losses over a set period. Lose $500 in a week with 10% cashback and you get $50 back. The calculation usually applies to net losses only, so if you deposited $500, won $200, then lost $700, your net loss is $500 and your cashback is $50.
The key question is whether the cashback comes with wagering requirements. "Real" cashback is credited as withdrawable cash with no strings attached. "Bonus" cashback is credited as bonus funds with a wagering requirement (typically 1x to 5x). Always check which type you're getting because the difference is substantial.
Cashback is generally one of the fairest bonus types available. It doesn't require you to win anything. It just softens your losses. If you're going to play regularly at one casino, look for a VIP or loyalty programme with solid cashback rates. Over months of play, the refunded losses add up to meaningful money.