An electrical receptacle assembly is mountable at an opening in a work surface to provide convenient access to electrical power and/or data. The assembly includes a main housing and a housing shell. The main housing defines an interior cavity for receiving a lower portion of an electrical or data outlet, and has an outlet opening in which a face of the electrical or data outlet is supported. The housing shell is coupled to the main housing and surrounds at least a portion of the interior cavity. Respective outer surfaces of the main housing and the housing shell cooperate to form an outer surface of the two-piece housing that is insertable into the opening in the work surface. A fastener, which may be an internally threaded collar, engages the two-piece housing, which may be externally threaded, and also engages the work surface, to secure the assembly to the work surface.