The present disclosure relates to electrical box assemblies and universal stabilizing brackets that can be used to stabilize electrical boxes attached to different size wall studs. The electrical box assemblies include an electrical box and a stabilizing bracket. Each stabilizing brackets includes a base, a front stop, a rear stop and one or more rear stop segments. The front and rear stops and the rear stop segments include a face member that extends substantially perpendicularly relative to the base. One or more notches are positioned at a junction between each rear stop to facilitate the breaking away of rear stop segments to modify the length of the stabilizing bracket.