10. Mesa Airlines
9/18Phoenix-based Mesa Airlines, which operates flights as American Eagle and United Express as part of agreements with American and United, respectively, voluntarily denied boarding to just 4,346 of the 10,345,895 passengers it transported between Q3 2019 and Q2 2020. The 42.007 per 100,000 passenger rate is higher than most major airlines but still well off of the leader's pace.