The Advertising Standards Authority has upheld one out of four complaints made by easyJet against rival Ryanair’s promotion of cheap flights.

The ASA ruled that the promotion of one-way fares from Stansted to Gothenburg and Dusseldorf-Weeze for £10 was “likely to mislead” as the fare was changed to £5 the day before the adverts were published.

Ryanair argued that more than half of seats to Gothenburg and 40% of seats to Dusseldorf-Weeze were booked at the £5 promotional rate during a four-day sale.

But the ASA found that the ads breached six clauses within the advertising standards codes. 

The authority threw out three other objections made by easyJet relating to add-on fees, promotional fare offer dates and a description of Weeze being 70km from Dusseldorf.

The ASA said the ads, published last year, should not appear again in their current form.

“We told Ryanair to ensure that all seats were available at the quoted fare, and if not all seats were available at the quoted fare, ads should state predominantly that fares were ‘from’,” the ASA adjudication said.

EasyJet UK general manager Paul Simmons said: “We welcome the ASA’s decision that one Ryanair advert broke six elements of the advertising standards code – that’s something of a record, even for them.”