Norwegian Air carried the highest number of passengers in June since the outbreak of the pandemic.
The Scandinavian budget carrier flew almost two million passengers last month, up by 19% over May.
The improvement came against the backdrop of a strike by aircraft technicians in Norway.
However, the airline struck a two-year collective bargaining agreement with the union representing the Norwegian cabin crew members and the Norwegian Pilot Union.
The June results came as rival SAS suffered a walk out by pilots and filed for Chapter 11 bankruptcy protection in the US.
Norwegian Air operated an average of 68 aircraft and 99.1% of scheduled flights were completed.
Chief executive Geir Karlsen said: “I am very satisfied that we operated almost 100% of our 400 to 450 daily scheduled flights this month.
“It has been a challenge due to a strike amongst aircraft technicians in Norway and the constraints at certain airports in Europe.
Strike action by aircraft technicians and a following lockout was ended when Norway’s labour minister announced compulsory arbitration.
Karlsen added: “We are satisfied with the agreement reached with our cabin crew and the Norwegian pilot union and we are also happy to have our aircraft technicians back at work to ensure that our flights are operating as normal.
“This means that we can deliver on the routes we have promised our customers.
“We are currently experiencing high demand this summer, but seats are still available to many destinations in Europe.”