The CITGO credit card will be a good option for you if you are going to fill up only at CITGO gas stations. However, you may not want to apply for this card if you have a habit of carrying a balance on your credit cards. The CITGO card comes with 24.99% APR which can eat up rewards you earn if you do not pay off the card balance each month. The 5 cents off per gallon offer is also not the most generous one. This offer can easily be beaten by a 2% cash back offered on the Discover it® chrome your first year. Plus Discover card comes with lower APR and a 14-month 0% interest introductory period (when the introductory interest rate is over, the ongoing APR will apply). If you prefer Visa cards the will allow you to earn 1.5% on all purchases, including gas purchases. As you see regular rewards credit cards offer bigger rewards and it means you will be able to save more on all your expenses.