A federal judge on Monday rejected United Airlines’ bid to dismiss a lawsuit ⁠by passengers who complained they paid extra money to sit in window seats – only to discover their seats ⁠had no actual windows.

US district judge ​James Donato in San Francisco rejected United’s defense that “window” referred to the location of a seat relative to the ⁠cabin wall and aisle, and the carrier also contended it never contractually promised that seats in the window position would have views outside.

Passengers filed proposed class actions against United and Delta Air Lines in ​August after finding themselves seated next ‌to walls on Boeing ‌737, Boeing 757 and Airbus A321 planes.

They said the carriers failed ‌to clearly disclose the missing windows during the booking process. Walls sometimes align with aircraft operating components, such as air conditioning ducts.

United, based in Chicago, declined to comment on the lawsuit. But the carrier said it has “added more detail to our seat selection process, so customers can have more information ‌about what to expect when they choose a seat”.

Lawyers for United passengers did not immediately respond to requests for comment.

​Delta is seeking to dismiss the lawsuit pending against it in the Brooklyn, New York, federal court.

Donato rejected United’s argument that federal law pre-empted passengers’ claims.

He also said United’s ticketing terms, boarding passes and reservation screens state expressly that the airline ⁠would provide window seats to passengers who paid for them. “No ​more is needed at this ​stage for the breach ​claims to go forward,” the judge said.

According to the ​plaintiffs, passengers typically ‌buy window seats to ​address fear ​of flying and motion sickness, keep children occupied, get more light, or take in the view.

Both lawsuits seek millions of dollars of damages, for more than 1 million passengers per carrier.