If you fly a lot and are consistent in your choice of airline, typically you can buy an unlimited-use pass that renews monthly for a flat fee. If you don't fly

If you fly a lot and are consistent in your choice of airline, typically you can buy an unlimited-use pass that renews monthly for a flat fee. If you don't fly often, I know you can prepay for a pass for your flight before leaving home on most services. Though for my use case (flying 75,000-85,000 miles/year on average) the monthly pass is absolutely cheaper.