Born in Rotterdam, Altheer began his career with Feyenoord; following a two-year loan spell with Excelsior, he left Feyenoord at the end of the 2008–09 season following the expiry of his contract.[3] He then signed for Helmond Sport in August 2009, on an amateur basis.[4] He signed a three-year contract with VVV-Venlo in May 2012[5] and joined Willem II in summer 2015.[6]
In April 2016 Altheer signed with ASWH,[7] where he finished his football career in October that year.[8] Since 2021, he plays for VV Lekkerkerk.[9]
International career
Altheer was a Dutch youth international, representing Netherlands at under-18, under-19, and under-21 levels.[10]