You can apply for a credit card with travel rewards. Such card will allow you to earn miles on all your purchases, including on flights with any airline. Earned miles can be redeemed with any airline of your choice, provided your airline ticket is bought with your travel rewards credit card. Since you are going to close your JetBlue card, you may want to apply for a travel credit card that also comes with a 0% intro APR on balance transfers. You will be able to transfer a balance from your old card and pay it off during a zero interest introductory period. Just remember that balance transfers do not earn rewards. Also, there may be a fee for balance transfers, which is usually around 3% of amount transferred. So, read the terms carefully before you apply.