Icelandair carried 198,207 international passengers in September - an increase of 18% year-on-year.
Capacity on international routes was increased by 17%, while load factor grew by 3 percentage points to 81%.
Passenger numbers on regional services and flights to Greenland - served by Icelandair Group subsidiary Air Iceland - fell 5% to 28,233 against capacity decreased by 6%.
Load factor grew by 4.1 percentage points to 70%.
In the cargo business, throughput for the group increased by 10% against capacity grown by 14%.