Alaska Airlines Grounds Flights After Major IT Outage

In a large scale disruption to air travel in the United States, Alaska Airlines and its regional partner Horizon Air ground all flights Sunday night due to a surprise IT outage. The ground stop began around 8:00 pm PT and suspended hundreds of flights which delayed and canceled travel everywhere in America.

Alaska Airlines confirms IT failure

Alaska Airlines said in their official statement, 

“On Sunday, at approximately 8 p.m. Pacific, Alaska Airlines experienced an IT outage that’s impacting our operations. We requested a temporary system-wide ground stop for all Alaska and Horizon Air flight while we work to restore our systems.”

pic.twitter.com/bM1F7mXZWY

— Alaska Airlines (@AlaskaAir) July 21, 2025

The airline advised travelers to expect residual delays and disruptions throughout the evening, even while operations were slowly returning to normal.

The Microsoft Hack: What We Know

Earlier Sunday, cybersecurity researchers reported that unknown attackers had taken advantage of a "significant vulnerability" in Microsoft's SharePoint collaborative software that can affect systems for various U.S. government agencies and private entities. The hack is regarded as one of the most serious described in recent years. Microsoft has not connected the hack to a disruption in operations within the airline industry.

Microsoft has acknowledged the exploit and is currently rolling out emergency patches to contain the impact.

Tweet Sparks Speculation: Was Microsoft Hack to Blame?

Alaska Airlines did not indicate a link to any cyber attacks, though a viral tweet from political commentator Chase Geiser is a little concerning in its suggestion of a related event in terms of timing, involving a vulnerability disclosed in Microsoft software that same day.

Tweet by @realchasegeiser

"The massive Microsoft hack we heard of earlier today is the reason Alaska Airlines has just grounded all its planes. Remember the F-35 that force-ejected the pilot and 'disappeared' for a day? ... And the Delta plane's engine blowing up in flames while taking off today? Welcome to AI Wars."

The massive Microsoft hack reported earlier today is the reason Alaska Airlines has just grounded all its planes.

Remember the F-35 that force-ejected the pilot and ‘disappeared’ for a day?

Did you notice the other one that crashed in Alaska earlier this year?

What about the… pic.twitter.com/atatXo3SQW

— Chase Geiser (@realchasegeiser) July 21, 2025

No Official Cyber Link—Yet

Although Geiser states otherwise, no federal agency, airline, or tech company has confirmed that the Alaska Airlines outage stemmed from the Microsoft data breach. Aviation experts say the timing is concerning, but do not want to speculate without facts.

Cybersecurity analyst Dr. Anita Freeman told NBC News: 

"It´s easy to connect the dots, but right now there is no reported connection. A caveat, however, is that aviation IT systems are extremely dependent on cloud services, often Microsoft-based, so it may be prudent to dig deeper into this."

Travelers Left Stranded

Airports globally including Seattle-Tacoma (SEA), Los Angeles (LAX), Denver (DEN), and San Francisco (SFO) reported long lines, confused passengers, and dozens of canceled or delayed flights. Customers complained they did not get timely notifications from the airline.

"I was about to board and suddenly they just announced there was a full ground stop. No explanation," said Jennifer Hall, a traveler stranded at SEA.

Flight Stats

Based on live data from FlightAware:

• More than 230 Alaska Airlines flights were either delayed or cancelled.
• By 10:30 p.m. PT, Horizon Air was over 70 delays.
• Travelers are advised to check their flight status prior to arriving at the airport on Monday morning.

What You Can Do

• Check your flight status regularly at alaskaair.com
• Follow social media updates from the FAA and the CISA
• If you are impacted, reach out to Alaska Airlines for rebooking or refunds

As Alaska Airlines continues to run its systems back online, the suspicions about the cause continue to grow. Though the Microsoft hack isn't specifically connected to the airline's outage, the tweet from Geiser shows a larger public anxiety that surrounds the growing overlap between cybersecurity, AI, and critical infrastructure.