Ryanair carried 5.3 million passengers in June, as European travel restrictions began to ease in the wake of the Covid-19 pandemic.
The figure compares with just 400,000 passengers in the same month last year, at the height of the outbreak.
However, numbers are still far below the 13.6 million passengers the low-cost carrier welcomed in June 2019.
Ryanair has carried 8.1 million travellers so far this year, with a load factor of 73 per cent.
The carrier, which recently debuted its first Boeing 737 Max, has been extremely critical of border closers in recent months, calling for a wider reopening.