Abstract: The filter cartridge locking assembly is configured to secure a collar within a housing of a filter cartridge. The collar includes first and second ends and fits into a circumferential retainer included on the housing. At least one notch is formed between the first and second ends of the collar for mating with at least one complimentary bead included on the retainer. An annular gap is defined on the collar for receiving a portion of the retainer. The retainer also receives a portion of the collar. The retainer is comprised of a first leg that extends radially outwardly and a second leg that extends substantially perpendicular to the first leg. The first and second legs interact with the collar in a surface-to-surface relationship while the at least one bead engages the at least one notch to form an axially and rotationally locked coupling between the housing and the collar.