Co-branded airline credit cards offer miles that can be redeemed for flights ... or you'll have to spend more points in order to pay for your flight. Try to be flexible with the days you're ...

Additionally, airline credit cards offer rewards when you use them ... it generally doesn't make sense to buy miles with your airline unless you're short a few thousand miles for an award ticket.

Delta Air Lines' Pay with Miles feature can help select American Express cardholders reach elite status faster — here's how.