Major US airlines recovering after technology issues caused problems

WASHINGTON — United Airlines and Delta Air Lines are recovering after experiencing a technology issue Monday that caused problems for travelers around the world.

Some passengers on social media reported delays as they tried to board aircraft and airlines' websites and apps appeared to, at times, not function properly.

On Tuesday afternoon, United Airlines' app and website said the airline was "working to fix a temporary technical issue affecting united.com and the United app."

"United encountered a brief technology issue connected to a vendor that prevented customers from logging into their MileagePlus accounts," United said in a statement. "The issue has been resolved and there was no impact to our flight operations."

Delta also confirmed it was experiencing technology issues on Tuesday and was working to return things to normal.

"Delta systems are stabilizing after a limited global technology issue that affected data connectivity to some of our systems behind-the-scenes," the airline said in a statement. "We appreciate our customers' patience and understanding."

The tracking site Down Detector indicated the American Airlines website and app were also experienced issues. However, the airline did not respond to CNN's request for comment.

The complicated IT technology used by airlines is made up of in-house systems as well as technology operated by outside vendors and used by multiple carriers. It's not clear exactly what went wrong on Tuesday, but airlines have had previous technology outages for several reasons.

In July, American was forced to halt flights for less than an hour due to an IT outage that "briefly impacted connectivity."

In August 2025, a technology issue prompted United to ground flights and caused over 1,000 delays and dozens of cancellations.

And most notably, in 2024, a software update for Microsoft Windows operating systems issued by the cybersecurity firm CrowdStrike brought systems down at businesses around the world. Delta, United, American Spirt, Frontier, Allegiant and Sun Country were among the airlines impacted.

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