Why would a bank insist I use the credit option when using a debit card?

So I just read about a program where chase will give you a small bonus for using your debit card to buy subway fare. However, they insist you use the credit option instead of the debit option when paying at a metrocard machine. As far as I know, I would be billed the same way (the money is deducted from my checking account) so what is the advantage to the bank here?|||As far as your bank account is concerned, it doesn't matter - both methods will correctly withdraw the appropriate amount.





However, businesses that accept credit cards must pay a small fee for every single transaction to the credit card company and/or bank (typically a percent or two of the purchase price). Historically this made sense, as any business that accepted Visa or Mastercard could increase their sales just by accepting credit cards. However, now that debit cards are widely accepted, the credit card banks are seeing their fees drop. So - they are doing what ever they can do to get more transactions cranking through their logo - thus increasing their fees.





So, the bottom line: The credit option makes more money for the bank. But it's a bit worse for the business, especially if it's a little one.|||The fee that your bank pays to the Transit Authority's bank is less.