There is no need to apply for an airline credit card. Airline credit cards usually give more rewards for ticket purchases from a particular airline and other purchases do not earn much. We would recommend you to apply for a regular credit card that will allow you to earn equal miles rewards on all your purchases. For example, it can be the Discover it® Miles card. The card will allow you to earn miles rewards and it comes with 0% intro APR on purchases (14.24% – 25.24% Variable after that). Another good feature is no annual fee. Most airline credit cards have high annual fees while Discover cards come without annual fees. Earned miles can be redeemed for any airline ticket with any airline, including with Southwest.