During February and March this year, the consulting firm IdeaWorks made 6160 queries across 22 frequent flier programs to assess reward seat availability for travel in June through October. Southwest ranked highest with 99.3% availability. US Airways and Delta were in the bottom two at 10.7% and 12.9%.
Most frequent flier programs award you a free domestic roundtrip ticket when you receive 25000 miles. They expire where there is no account activity over a period of time usually 1 year. Travelers can go many years without redeeming awards if they fly the same airline once a year.
Southwest operates differently. Refer to Why Fly Southwest Airlines. Instead of miles, they award 1 credit for each one-way flight. You are awarded 2 one-way flights when you reach 16 credits within 24 consecutive months. If you are unable to use your award within 12 months, your award expires unless you pay $50 to reissue the award.
You may consider the Southwest expiration policies as negatives but you can always rely on them for last minute flights with many connection options. It is also easy to give away the award to another person.
When frequent flyers redeem awards at a constant rate, availability is more manageable. When awards do not expire, you may go through periods of high supply or high demand.
Other notable airlines
- American - 57.9%
- Continental - 71.4%
- United - 68.6%
