There are cash back credit cards with low interest rates and with 0% intro APRs. These credit cards will allow you to earn cash back on gas purchases and on all other purchases. You can also find credit cards with sin up bonuses. Your ongoing interest rate will be determined by a credit card issuer based on your creditworthiness. So the better your credit score is, the lower your interest rate will be. But remember, you can avoid interest payments by paying off the card balance during grace period. Therefore, to maximize the card savings we recommend you to pay off the card balance every month.