If I spend a certain amount of money on my credit card within the first 3 months I get a cash bonus from the credit card company. if I let someone use my credit card do I need to give them the cash bonus percentage of what they spent(assuming that I needed their spending to reach my goal that I had to spend to get the bonus)or can I keep it all myself? Are there any issues of ribis? Also if not too difficult can you please provide a source so that I can see it inside? thankyou
When you give someone your credit card to use, essentially you are borrowing the money from the credit card company, you are the one liable to pay it back, and you are also lending that money to your friend. Therefore if there are any interest charges to this charge you may not pass that charge on to your friend, unless you have a valid heter iska. The credit card company gives a bonus for their customers, because they want them to spend money on the card (and possibly pay a lot of interest). This being the case, it is clear that the point belong to the credit card holder, as the company is giving him the points for using his credit card.
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Bris Yehuda (Ikkrei Dinim 14:25) and by Nesivos Shalom (174:4:57).