United Airlines tech outage grounds hundreds of flights across US hubs

United Airlines announced that it was holding all mainline (non-regional) flights at departure airports due to a 'technology issue'. Services later resumed gradually

United Airlines temporarily grounded its mainline flights across the United States on Wednesday evening (local time) following a major technology outage that affected several of its busiest hubs, including Chicago, Denver, Houston, Newark, and San Francisco.

 

The airline confirmed late Wednesday that the issue had been resolved and operations were gradually returning to normal, although residual delays were expected.

 

“We are working with customers to get them to their destinations after a technology disruption on Wednesday evening,” a United spokesperson told CNN. “The underlying technology issue has been resolved, and while we expect residual delays, our team is working to restore our normal operations.”

 

Major flight disruption across US

According to real-time flight tracking service FlightAware, approximately 31 per cent of United’s flights were delayed and 1 per cent were cancelled by 9.45 pm Eastern Time (ET). Earlier in the evening, the airline had announced that it was holding all mainline (non-regional) flights at departure airports due to a “technology issue”. Flights already airborne were not affected, and United Express (regional) flights continued to operate.

 

Impact on passengers and response

Passengers across several US airports reported hours-long delays, with many describing a lack of clear communication and growing discomfort. At least one flight departing from Nashville was held on the tarmac due to missing data required for takeoff, highlighting how the outage had disrupted essential pre-flight systems.

 

United Airlines did offer affected passengers hotel accommodations and rebooking options for the following day as the airline worked to manage the cascading impact of the system failure.

 

Aviation authority confirms ground stops

The US Federal Aviation Administration (FAA) confirmed the incident, showing multiple ground stops issued at around 7.30 pm ET at United hubs. Ground stops are orders to halt departures, typically issued during emergencies or critical system failures.

While United has not provided technical details on the nature of the system failure, the disruption comes just weeks after Alaska Airlines faced a similar IT outage that grounded its entire fleet. In April 2024, Alaska Airlines also halted operations due to a malfunction in its weight and balance calculation system, a critical component for safe aircraft operation.

 

United Airlines records 174 million passengers

United Airlines, one of the largest carriers in the US and a member of the Star Alliance (which includes Air India), operates numerous international routes, including to and from Indian cities such as Delhi and Mumbai. 

The airline carried a record 174 million passengers during 2024 and reported the highest on-time departure rate across its seven US hub airports. 

It reported pre-tax earnings of $4.2 billion for the full year 2024, with an adjusted pre-tax margin of 8.1 per cent. Net income was $3.1 billion, while adjusted net income came in at $3.5 billion. Diluted earnings per share stood at $9.45, or $10.61 on an adjusted basis, near the upper end of the airline’s full-year guidance.

 

Total operating revenue rose 6.2 per cent year-on-year to $57.1 billion, driven by growth across fare types. Revenue from its basic economy class rose by 20 per cent, while premium cabin revenue went up by 10 per cent.

 

As of Thursday morning (IST), United’s website and mobile app were operational, and services appeared to be stabilising.