American has 132 A319 aircraft in the fleet with two different versions. Aircraft 001 to 032 are A319S that were originally delivered to American. Those A319 are "advanced", as in short field and high altitude performance capabilities and an enhanced interior. The A319S all have seatback screens for entertainment and Viasat satellite Wi-Fi. This fleet all has Sharklets and is powered by the CFM International CFM56-5B7/P engines.

N700UW to N770UW are all Legacy US Airways, N771XF to N778XF were all acquired from Frontier Airlines, and N801AW to N840AW were all legacy American West aircraft. The legacy USAir and Frontier fleet is powered by the CFM56-5B3/P engines while the legacy America West fleet is powered by the IAE V2533-A5 engines. All 3 use wingtip fences and are equipped with Gogo's 2Ku satellite Wi-Fi and IFE onboard is free to stream on your personal device. Every seat has power ports. There are 8 First Class seats, 24 Main Cabin Extra, and 96 Main Cabin seats

On March 4, 2024, American Airlines announced it will retrofit the A319 and A320 fleets with an enhanced cabin featuring more premium seats. The first aircraft to get the retrofit will be the 32 a319s in late 2025