Ryanair plans to reintroduce 40% of its flights from 1 July, subject to travel restrictions being lifted and safety measures being brought in at airports.
The airline will operate nearly 1,000 flights a day, bringing back 90% of its regular timetable.
Since restrictions began in March, Ryanair has only operated 30 flights a day between Ireland, the UK and Europe.
British Airways is going to review its plans to run 50% of its schedule from July, because of new quarantine rules.
Ryanair will ask its passengers to check in online and bring fewer bags, while they will also have to download their boarding pass to a smartphone.
On arrival at the airport, people will have their temperature checked and will have to wear a face mask or covering at all times in the terminal and on planes.
The company says it uses air filters in its planes similar to those used in critical hospital wards and that all interior surfaces in planes are disinfected every night.
During flights, passengers will not be allowed to queue for the toilet, and instead will have to request access.
Cabin crew will wear face masks or coverings and only a limited in-flight pre-packed food and drink service will operate, with all transactions being cashless.