While flight delays can be a source of frustration for travelers, understanding the factors behind them provides insight into airline operations. The three largest airlines in the United States—United Airlines, Delta Air Lines, and American Airlines—each operate vast fleets and face their own challenges with delays.
According to the Bureau of Transportation Statistics (BTS), from January to April 2025, American Airlines had 76.3% of its flights arrive on time, with 21.4% delayed, 2.0% canceled, and 0.3% diverted. Delays were primarily due to late-arriving aircraft at 8%, air carrier delays at 6.4%, and national aviation system delays at 6.3%.
Delta Air Lines recorded a higher on-time performance with 80.2% of flights arriving as scheduled during the same period. Their delayed flights accounted for 18.5%, cancellations for 1.0%, and diversions for 0.2%. CBS News ranks Delta as having few cancellations and no involuntary bumping incidents.