Icelandair Group carried 148,000 international passengers in April, marking an increase of 9% year-on-year.
Capacity on international routes rose by 20%, while load factor fell by 5.1 percentage points to 76.2%.
Passenger numbers on regional services and flights to Greenland - which are served by group subsidiary Air Iceland - fell by 5% to 25,400, against a capacity drop of 10%.
The load factor on regional and Greenland flights rose by 3.3 percentage points to 69.3% for the month.
On the cargo front, FTK throughput and ATK capacity for the group grew by 5% and 11% respectively.