A filter assembly for a refrigerator appliance includes a filter housing and a filter locking mechanism pivotally mounted at least partially within the filter housing. The filter locking mechanism includes a locking arm defining a retention clip and a resilient arm that extends from the locking arm at an extension angle of less than 90 degrees. As a filter cartridge is inserted into the filter housing, the resilient arm acts like a spring to urge the filter cartridge out of the housing. After the filter cartridge passes or engages the retention clip, the spring force from the resilient arm urges the filter cartridge against the retention clip to secure the filter cartridge within the housing.