A visit to Southwest Airlines website Wednesday afternoon was turning up what the airline is calling a "waiting room" page where visitors weren't able to book flights.
The outage was leading to nationwide delays, ABC News and CBS News both reported.
A message on Southwest's website told visitors to not refresh browsers and that visitors would be automatically transferred to Southwest.com as soon as possible.
On the airline's official Twitter page, Southwest tweeted: "We are aware and investigating current issues with our systems. We will keep you posted as we have more information to share."
The airline also tweeted that it's "working hard on a fix" to the waiting room page problem.