Ryanair said it flew a total of 10.6 million passengers in September of this year as Covid travel restrictions eased.
The airline had carried 5.2 million passengers the same month last year.
It said its load factor - how many seats it fills on each flight - rose to 81% from 71%.
Ryanair said it operated over 69,500 flights in September.
Its shares were higher in Dublin trade today.
Meanwhile, Hungarian low cost airline Wizz Air also said its September passenger numbers were 91% higher and it flew 57% more seats compared to the same month last year, when pandemic restrictions were still having a much bigger impact on travel.
Wizz said it carried almost 3 million passengers in September with its planes flying at about 78.4% full.