Anderson is a product of AGF and Reynir Sandgerdi where he played before joining FC Midtjylland as U14 player.
[5] He made his professional debut in the Danish Superliga for Midtjylland on 4 December 2016 in a game against AGF.
[6] On 31 August 2017, Anderson was loaned out to Vendsyssel FF in the Danish 1st Division for the rest of the season.
[7] He scored the winning goal in a 2–1 victory against Lyngby BK and secured a promotion to the Superliga for the first time in the club's history.
[11] On 15 December 2017 he was called up to the senior Iceland squad for two friendlies against Indonesia in January 2018.