Seattle-Tacoma International Airport is experiencing system failures that may impact flight operations following a potential cyberattack on the Port of Seattle over the weekend.

Shortly after 9 a.m. PT on Saturday, the airport announced on X (formerly Twitter) about the potential attack, stating they had “isolated critical systems.” However, as of their update in the afternoon, they could not provide a timeline for when those systems would be back online.

As of 11 a.m. PT on Sunday, the airport’s website remained down.

On Sunday, the airport communicated via X that while their teams were making progress in restoring systems, there was still no estimated time for full recovery.

Impact of Possible Cyberattack on Flight Schedules

On Saturday, there were 165 flight delays and six cancellations. As of 11:30 a.m. PT on Sunday, there were 116 delayed flights and four cancellations, according to FlightAware. It is unclear whether the system outages directly caused these delays.

Travelers are encouraged by the airport to verify flight statuses with airlines, check in online, and avoid checking bags if possible.

Representatives from Delta Airlines and Alaska Airlines, which both use Seattle Tacoma as a major hub, informed the Seattle Times that their operations remained largely unaffected on Saturday.

Alaska Airlines stated to YSL News that their systems were working as usual, but they had started to experience some issues with the Port of Seattle’s baggage sorting system. They advised customers flying out of Seattle to refrain from checking bags if they could.

Delta Airlines reported that any operational disruptions at the airport on Sunday were minimal.

These outages follow a significant Crowdstrike system failure in July, which resulted in thousands of flight cancellations nationwide due to impacts on airline booking and scheduling systems.