Abstract: An underseat container system can be positioned between a seat and a floor of a vehicle, and can include an open-topped receptacle or container. The receptacle can be secured to the vehicle seat via a cable lock system, the cable lock system including a cable and a cable lock mechanism. When the receptacle is placed under the vehicle seat, the cable can be threaded through an aperture in a wall of the receptacle, and around a support member in the seat. The cable lock mechanism can secure the threaded cable to itself, thus securing the receptacle to the vehicle seat. When the vehicle seat is configured to accept passengers for seating, the vehicle seat and the receptacle can form a storage compartment. The receptacle can include a plurality of nubs on its bottom surface, for providing traction to the underseat container when positioned underneath the vehicle seat.