The airline said it had drafted in pilots from elsewhere to fill in during the industrial action and would inform passengers of any changes to their flights by email and text message.
“Our flights are scheduled to operate, if your flight is affected you will receive an email and a text message with all the details,” the airline said. It recommended customers check its website.
The airline lost its High Court bid in London on Wednesday to stop the strike action by some of its British pilots.
Justice Lambert DBE rejected Ryanair’s arguments and ruled the British Airline Pilots Association’s (BALPA) industrial action ballot and procedures were lawful.
Balpa said it offered an “olive branch to Ryanair as a way of moving forward” but said it was rejected by the airline.
Another 48-hour walkout is planned by the union to coincide with the end of the summer holidays.
Earlier on Wednesday, the airline won a separate legal battle in the Irish High Court to prevent its Irish pilots from striking on the same days.
More: Ryanair loses High Court bid to block British pilots strike
Ryanair granted injunction preventing Irish pilot strike
