The present subject matter provides a gas burner assembly for an appliance. The gas burner assembly includes a burner tube and a shutter slidably mounted to an end portion of the burner tube. The shutter defines a slot with an axially extending portion. A boss is mounted to the tubular burner and is received within the slot of the shutter. The boss is movable within the axially extending portion of the slot in order to permit the shutter to slide along an axial direction on the burner tube. Such features can facilitate access to an orifice of the gas burner assembly.