JetBlue Airways said it had fixed a systemwide computer problem by 6:15 a.m. Eastern that has caused delays because the airline had to manually check in passengers.
NBC News reported that the airline had to issue handwritten boarding passes to passengers at many airports.
The company said in an email that passengers might experience delays throughout the day. It did not specify how long it would take to work through delays and get operations back to normal.
The airline did not immediately respond to inquiries on how many flights were affected, but passengers at airports in Boston; Orlando, Fla., and Washington, D.C., took to social media to report long lines and delays.
A list of flights on the website of New York's John F. Kennedy International Airport, JetBlue's busiest airport, showed delays of 60 to 90 minutes for early morning flights and numerous delays but there were shorter delays for more recent flights.