By Megan Cerullo
February 2, 2026 / 6:56 PM EST / CBS News
United Airlines plans a major technology upgrade that will take its online reservation system offline early Wednesday. The carrier is asking passengers with Wednesday flights to check in via United’s website or mobile app on Tuesday to avoid problems. United expects the outage to last about four and a half hours, from 2:30 a.m. EDT to 6 a.m. EDT.
An alert on United’s homepage says the airline is “conducting a planned technology upgrade” and that many web and app services will be unavailable during the window — including tools used by airline employees.
United is modernizing its aging mainframe reservation system, known as Shares. The update requires transferring reservation data from its current North Carolina data center to a more advanced facility in Chicago, a move the airline says will improve reliability.
What if I am flying on Wednesday?
United’s flight schedule and many online functions will be temporarily unavailable early Wednesday. During the outage customers won’t be able to make new reservations, cancel bookings, check in, retrieve itineraries or use many online services. For that reason, the airline urges anyone flying Wednesday to check in on Tuesday and, if needed, check bags then (passengers can typically check bags up to four hours before departure).
The refresh has been planned for months; United previously canceled about 600 affected flights and notified customers. Travelers can still book, check in or change trips before Feb. 4 at 2:30 a.m. EDT, or after the data transfer is finished.
What could go wrong?
United says it has rehearsed the migration process and expects the transfer to go smoothly. Travel experts likewise predict limited disruption. “Don’t freak out if you can’t search for flights in the middle of the night,” Scott Keyes, founder and CEO of flight-deals site Going.com, told CBS News. “It will come back online soon.”
However, if the upgrade encounters problems it could create customer headaches. A decade ago, a major computer outage at Southwest Airlines lasted days and caused hundreds of cancellations and thousands of delays.
Edited by Alain Sherter
Kris Van Cleave contributed to this report.