Ryanair traffic rose by 30 per cent from January 2014 to the same month this year, according to new figures published on Wednesday.
The airline said it carried an additional 1.3 million passengers last month, giving it a total of 5.98 million customers in January, compared to 4.6 million for the same month a year earlier.
Ryanair said rolling annual traffic to January 2015 grew 8 per cent to 87.8 million.
Load factor - a measure of how many seats are filled on each flight - rose 12 per cent to 83 per cent, compared to 71 per cent for the same month last year.
The airline attributed the rise in customers and load factor to lower fares and the success of its ‘Always Getting Better’ customer programme, which it said delivered strong forward bookings.