The airline halted all departures at all US airports on Thursday due to a system failure.
The US carrier said in a statement that it was "experiencing an system disruption affecting operations" and issued "an operational pause."
The airline did not say how long the disruption would continue or the number of flights were affected. It stated it was "actively restoring our operations" following the outage.
The operational halt also impacted the regional carrier, which is a subsidiary of the parent company, according to an notice by the aviation authority.
Alaska Airlines, part of The airline group based in the Pacific Northwest, mainly serves on the western seaboard of the US. It services numerous locations worldwide, including multiple states and dozens of nations, as stated on its website.
Previously, the airline joined forces with another carrier, which was not impacted by the day's flight suspension.
It is the second IT outage affecting the airline in recent months. In July, an issue disrupted operations for about several hours.
The company did not provide a comment on the day to requests for comment.
Air transportation in the US has been complicated in recent weeks due to the US government shutdown that began earlier this month. Lack of flight controllers reporting for duty has caused delays at multiple locations.
