United Airlines surpasses American Airlines with largest mainline fleet

On the Boeing side, American operates a total of 516 aircraft. Its Boeing fleet supports both high-density domestic routes and long-haul international services. The workhorse is the Boeing 737-800 for short- and medium-haul flights; meanwhile, the widebody segment includes both the 777 and 787 series—67 in total—with the highest-capacity model being the Boeing 777-300ER.

American Airlines is headquartered in Fort Worth, Texas, with major hubs across Dallas/Fort Worth International Airport (DFW), Charlotte Douglas International Airport (CLT), Miami International Airport (MIA), Phoenix Sky Harbor International Airport (PHX), and Los Angeles International Airport (LAX). In 2024, it carried approximately 248 million passengers.

United Airlines’ fleet shows a different composition: its Airbus fleet is smaller at just under 200 aircraft but is growing due to significant orders for models such as the A321neo and A321XLR. Additionally, United has ordered its first widebody Airbus type—the A350-900.

The bulk of United’s mainline operation relies on Boeing aircraft. The airline operates various models ranging from narrowbodies like the Boeing 737 family—including MAX variants—to widebodies such as the Boeing 767s, 777s, and all three Dreamliner types (787-8/9/10). In total, United’s Boeing mainline fleet numbers over 800 units.

United maintains several hubs across the US; Newark Liberty International Airport serves as its primary transatlantic gateway while San Francisco International Airport anchors its transpacific operations. Recent network expansions have included new destinations such as Adelaide in Australia and Bangkok in Thailand.

Delta Air Lines remains close behind both rivals with a current mainline fleet size of about 990 aircraft.

A review of current orders suggests that United will likely maintain or increase its lead over American in terms of overall fleet size for at least several years to come.