Celtic Casino provides you with the option to receive a cashback bonus based on your first deposit upon signing up. It means that this applies to new real money account players.
The bonus consists of a 50% CashBack up to 100 euros. You must deposit at least 50 euros for this to apply and there is a wagering requirement of 35x. The WR apply only to the bonus given.
Players only have seven days after losing the initial amount to apply for this reward. After the seven days have passed, the bonus is no longer available for the player.
The bonus code is "50% Cash Back" and should be the on the subject line of the email when making the request. You can also talk to a live agent and requested through there. Here is the complete link to their full review.