Ryanair carried seven million passengers in January 2022.
This was up from 1.3 million in the same month of 2021, but a drop compared to December as restrictions to tackle the Omicron variant.
The carrier operated more than 46,400 flights last month, with a 79% load factor.
Last month’s figure was a drop from 9.5 million passengers in December, which also saw a higher load factor of 81%.
The airline noted that traffic in December and January was “badly affected by Omicron travel restrictions”.
On Monday, Ryanair announced a group loss of €96 million for the three months to December.
It cut its January programme by 33% because of the Omicron restrictions and expects the first half of February to be weak.