Ryanair Group year-on-year passenger carryings more than doubled in July to 9.3 million.
The improved performance last month was put down to the introduction of the EU Covid-19 vaccination certificate.
The increase followed the budget airline parent company flying 4.4 million passengers in the same month last year during the first stage of the pandemic.
Ryanair operated more than 61,000 flights in July with a load factor of 80%.
The July figures represent an improvement on the 5.3 million carryings in June when the load factor was 72%.
The figures came a day after rival low fares carrier Wizz Air revealed that it flew almost three million passengers in July as it continued to rebuild its network.
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