Abstract: Folding buckle clasp (1) designed to be attached to two bracelet strands or to a one-piece bracelet at two locations on the latter, comprising: ?-a first clasp element (3); ?—a second clasp element (7) hinged to said first element (3) via a hinge (9); ?—a locking system designed to keep said clasp in a folded-up state and to make it possible to put said clasp into an unfolded state in response to an action by a user; the locking system having ?—a spring-loaded pin (19) comprising a tubular body (19a) and at least one retractable stud (25) protruding axially from the tubular body (19a), said retractable stud (25) being subjected to a return force (F) that tends to keep said retractable stud (25) in an extended position, said pin (19) being situated in said first clasp element (3); ?—a cover (11) that is fastened to said second clasp element (7) and comprises at least one opening (27) having a shape corresponding to the retractable stud (25), said opening (27) being made in an inner face (11a) of the cover (11)