Ryanair said its passenger numbers rose by 7% to 12.6 million customers in June.
The airline said its load factor - how many seats it fills on each flight - remained at at 96% during the month.
It also noted that air traffic control strikes and staff shortages caused over 1,100 flight cancellations in June compared to just 41 cancellations the same time last year.
The airline today repeated its call for action from Europe to help tackle disruption from the strikes.
"Ryanair calls for urgent action by the EU Commission and European governments to ameliorate the effect of ATC strikes and staff shortages in the UK, Germany and France from disrupting the travel plans of millions of Europe's consumers this summer," its chief marketing officer Kenny Jacobs said.
EasyJet has also revealed the impact of the strike woes in recent weeks, cancelling nearly 1,000 flights in May, as widespread thunderstorms also took their toll.
Air traffic control strikes are costly for airlines and hugely disruptive for passengers, especially in France, as many UK and Irish flights need to use the country's air space or fly longer routes to avoid it.
But ATC action has become a regular headache for the industry in recent years, with 2017 said to be a record for strikes, with 41 days affected.