United Airlines Tech Outage Grounds Flights Nationwide, Compounds Storm Delays
United Airlines' reservation system failed for roughly 75 minutes on the morning of July 18, 2026, freezing check-in and boarding at hub airports across the country. The outage, combined with severe East Coast storms, contributed to a nationwide total of 2,437 canceled U.S. flights that day, with United posting the highest delay rate of any major carrier. Disruptions and above-average cancellations carried into the following day as the airline worked through its backlog, leaving thousands of travelers scrambling to rebook during one of the summer's busiest travel stretches.
What Knocked Out United's Systems
Cause: SHARES reservation system failure · Outage window: 6:00–7:15 a.m. Central Time, July 18
United confirmed the fault originated in its SHARES reservation system, the backbone that processes check-in, ticketing, and bag-drop functions fleet-wide. The airline told Simple Flying the issue was isolated to United and unrelated to any cybersecurity incident, and Down Detector logged more than 430 user reports within the first 45 minutes of the outage. AeroXplorer's coverage noted that once the fault was traced, United's IT team restored the system within roughly an hour, a relatively fast recovery for an outage of that scale.
Which Airports Felt It First
Hardest hit: Washington Dulles, Newark Liberty, San Francisco, Houston Bush Intercontinental
Gate agents at Dulles and Newark switched to manual check-in as the system stayed down, and Houston's Bush Airport confirmed disruptions to KPRC Click2Houston before the Houston Airport System declared the carrier's systems operational again. Business Insider reported similar check-in slowdowns at other United hubs that same morning. No aircraft already airborne were affected, since the fault sat in ground-side ticketing rather than flight operations.
How United Compared to Other Airlines That Day
United's toll: 1,261 delays (39% of flights) · 268 cancellations (8% of flights)
United logged the highest percentage of delayed flights among major U.S. carriers on July 18, narrowly trailing American Airlines' 1,280 delays in absolute terms, according to TheTravel's FlightAware analysis. Southwest (1,169), Delta (951), and SkyWest (586) rounded out the list, with weather over the New York area compounding United's tech problems industry-wide.
What United Is Offering Affected Travelers
Relief offered: Fee-free rebooking for East Coast hubs, extended through July 19
United said on X that "operations are returning to normal after an early morning technology issue," and issued a rebooking waiver covering Hartford, Boston, Baltimore, Washington (DCA and IAD), Newark, LaGuardia, Philadelphia, and Providence, letting ticketed passengers change flights without a fare difference. Delays continued into July 19, when Delta reported 275 cancellations, JetBlue 150, and American 114, according to FlightAware-tracked figures, while United's own cancellations dropped to triple digits as crews and aircraft repositioned.
People Also Ask
What caused the United Airlines outage on July 18, 2026?
A failure in United's SHARES reservation system, which manages check-in, ticketing, and bag-drop, went down at 6:00 a.m. Central Time and was resolved by 7:15 a.m. United confirmed the issue was a technical fault unrelated to any cyberattack, and no aircraft already in the air were affected by the disruption.
How many United Airlines flights were canceled?
United canceled 268 flights and delayed 1,261 more on July 18, 2026 — about 8% and 39% of its schedule, respectively. Disruptions continued into July 19 with additional cancellations as the airline worked through its backlog, though the numbers dropped to double and triple digits by the next morning.
Which airports were most affected by the United outage?
Washington Dulles, Newark Liberty, San Francisco International, and Houston's George Bush Intercontinental saw the heaviest check-in and boarding disruptions. Gate agents at several hubs switched to manual processing while the reservation system was down, slowing bag drop and boarding lines nationwide.
Can I get a refund if my United flight was delayed by the outage?
United offered a fee-free rebooking waiver for tickets through East Coast hub airports rather than automatic refunds. Passengers whose flights were canceled outright are generally entitled to a refund under U.S. Department of Transportation rules; those merely delayed should check United's current advisories for applicable rebooking terms.
Was the United Airlines outage related to a cyberattack?
No. United and aviation officials confirmed the July 18 outage stemmed from an internal fault in the SHARES reservation system, not a cyberattack or the broader air traffic control network. The airline said its teams resolved the underlying issue within about 75 minutes.
Facts checked against current sources as of July 20, 2026. Flight statistics and airline policies change quickly — confirm current status directly with United before traveling.
