Lukas Karlsson started playing handball at IFK Nyköbing in his hometown.
He then joined Danish club Viborg HK until 2009 when he switched to league rivals KIF Kolding.
[5] At the end of his career he joined Norwegian second tier side Follo HK.
[6] From the 2022-23 season he retired as a player and became the headcoach of Follo HK.
[7] Karlsson is married to Norwegian international Ida Bjørndalen.