A stud mounting bracket for a junction box includes a mounting extension extending outward from a longitudinal end margin of a main body. The mounting extension includes a mounting body connected to the longitudinal end margin of the main body and an extension tab connected to the mounting body. The extension tab is pivotable relative to the mounting body about an axis from a compact configuration to an extended configuration to increase the length of the mounting extension. A box mounting bracket for mounting a junction box on a stud mounting bracket includes first and second jaws. The first and second jaws engage the stud mounting bracket for use in attaching the box mounting bracket to the stud mounting bracket. The first and second jaws are resiliently deflectable both relative to the base and independent of one another when attaching the box mounting bracket to the stud mounting bracket.