Largest Airlines at TUS (Dec 2015 – Nov 2016)[32] Rank Airline Passengers Share 1 Southwest Airlines 976,000 30.94% 2 American Airlines 705,000 22.36% 3 SkyWest Airlines 681,000 21.61% 4 Mesa Airlines 263,000 8.33% 5 Delta Air Lines 246,000 7.79% 6 Others 283,000 8.97%