A window balance assembly may be in a window jamb channel to provide a biasing force urging a window sash toward an open position. The window balance assembly may include a carrier, a spring element and a mounting bracket. The spring element may include first and second portions. The first portion may be coupled to the carrier. The mounting bracket may include a latch, a first head portion, and a first projection. The latch may engage the second portion of the spring element. The first head portion may be configured to abut a first wall of the window jamb channel when the window balance assembly is installed in the window jamb channel. The projection configured to extend through and engage an aperture in a second wall of the window jamb channel when the window balance assembly is installed in the window jamb channel.