American Airlines said its passenger traffic in September dropped 0.2 percent as the airline increased its capacity by 1.6 percent.
The company said its load factor also decreased 1.5 percentage points to 80.0 in September.
American said it expects unit revenues to be up 0.5 percent to 1.5 percent for the third quarter and estimates its pre-tax profit margin excluding special items will be in the 10 to 12 percent range.
In an investor filing made on Wednesday, American said it expects total capacity to be up 2.2 percent compared to 2013 as it adds larger aircraft to the fleet while retiring smaller planes.
American has about $8.8 billion in cash and short-term investments as of September 30.