I have a bank account which gives a certain amount of cash back for every transaction, similar to most credit cards which offer 1-2% of each transaction as cash back. I use this account exclusively for my maaser money. What is the status of the cash back that I get from this account? Does it belong to maaser or is it mine?
From what you are explaining it sounds like they are paying you for the money that you are keeping in the bank account. Which would really be paying you for investing your maaser money with their bank. Since this is a way that the maaser money is earning money, the profits would belong to maaser.
Bais Din Shel Shlomo Y:D 1-1-23, Borach Tzedakah 11-73..