The invention relates to a snap-on fixing (10) for fastening a thin wall (14), such as a housing wall, door leaf, flap or the like, which is provided with a passage (13) on a wall support (16), such as a housing frame, door frame, wall opening edge or the like, which is also provided with a passage. Said snap-on fixing comprises a base part (18) that can be fastened in the passage (12) of the wall support (16). A head part (20) extends away from said base part (18) and has, across its longitudinal section, a cross-section (49) that first increases and then decreases from the end of the head part (20) towards the base part (18). The head part (20) represents a male push-in part that is received, while overcoming a spring force (28) that is effective radially outwards in the direction of the diameter (49), by an undercut female push-in part (13), configured or carried by the passage (13) of the thin wall (14). The inventive snap-on fixing is characterized in that the head part (20) represents a guide or channel for one or more pushing or retaining elements (22, 23) that are pushed by at least one spring (28) into a position that projects beyond the end of the guide or channel. The ends (51, 53) of these elements projecting from the guide or channel have a triangular or spherical shape in a plane of projection perpendicular to the thin wall (14).