The refunds will apply to people who bought their ticket before the FAA shutdown began on July 23, but who traveled after that day. During the shutdown, airlines stopped collecting federal taxes that can add up to $60 on a $300 round-trip ticket.
Delta says it is waiting for guidance from the IRS about how to handle the refunds.
Most airlines raised fares by the amount of the taxes, so travelers are paying the same now as they did before the FAA shutdown. The airlines are collecting some $30 million a day in higher fares during the FAA shutdown.