"Alaska Airlines is experiencing an IT outage affecting operations. A temporary ground stop is in place. We apologize for the inconvenience," the Seattle-based company said on X.

"If you're scheduled to fly tonight, please check your flight status before heading to the airport."

The ground stop also affects its subsidiary Horizon Air, according to the US Federal Aviation Administration.

Three hours after the announcement was made, some passengers complained about a lack of information.

"Everyone everywhere at SeaTac. No boarding no firm updates," said one X user, Jeff Lawrence, posting a picture of a jam-packed airport waiting room.

Alaska Airlines, the fifth-largest US carrier, experienced a similar outage on July 20, which lasted about three hours.

Alaska Airlines attributed the July problem to the failure of "a critical piece of multi-redundant hardware at our data centers."

Alaska last year also experienced an IT outage that caused disruption and delayed flights.

In January 2024, a door plug section of a new Boeing 737 Max 9 blew out during an Alaska Airlines flight between Portland, Oregon and Ontario, California.

The 171 passengers and six crew members survived the rapid decompression, but the FAA temporarily grounded many Boeing 737-9 aircraft operated by US airlines.