A washing agent dispenser for a washing machine, in particular a dishwasher, including a dispenser body configured to be mounted to a wall delimiting a washing chamber of the washing machine, said dispenser body having a receptacle adapted to contain a washing agent, a cover mounted in a guided manner to the dispenser body in such a way to be movable relative to the dispenser body along a sliding direction, between a closed position in which the receptacle is closed by the cover and an open position in which the receptacle is open, and sliding guides interposed between the cover and the dispenser body, and comprising first guide elements (21, 22, 23, 25; 21', 22', 23') arranged on the dispenser body and second guide elements (31, 32, 33, 34, 35; 31', 32') arranged on the cover and coupled to the first guide elements (21, 22, 23, 25; 21', 22', 23'), wherein the cover comprises a frame carrying the second guide elements (31, 32, 33, 34, 35; 31', 32') and a shell assembled or joined to the frame, wherein a gasket adapted to engage an edge of the receptacle of the dispenser body is arranged on the frame, wherein the dispenser further comprises a latching system interposed between the shell and the dispenser body and configured to hold the cover in the closed position, said latching system being operable to release the cover allowing the cover to move from the closed position to the open position, the dispenser being characterized in that the frame is connected to the shell by means of at least one deformable connection element of material having lower stiffness than the material(s) of the shell and the frame, said deformable connection element being arranged in such a way that the shell is movable in a limited manner relative to the frame along the sliding direction, the shell being movable with respect to the frame by an extent much smaller than that of the stroke between the open position and the closed position of the cover. a dispenser body configured to be mounted to a wall delimiting a washing chamber of the washing machine, said dispenser body having a receptacle adapted to contain a washing agent, a cover mounted in a guided manner to the dispenser body in such a way to be movable relative to the dispenser body along a sliding direction, between a closed position in which the receptacle is closed by the cover and an open position in which the receptacle is open, and sliding guides interposed between the cover and the dispenser body, and comprising first guide elements (21, 22, 23, 25; 21', 22', 23') arranged on the dispenser body and second guide elements (31, 32, 33, 34, 35; 31', 32') arranged on the cover and coupled to the first guide elements (21, 22, 23, 25; 21', 22', 23'), wherein the cover comprises a frame carrying the second guide elements (31, 32, 33, 34, 35; 31', 32') and a shell assembled or joined to the frame, wherein a gasket adapted to engage an edge of the receptacle of the dispenser body is arranged on the frame, wherein the dispenser further comprises a latching system interposed between the shell and the dispenser body and configured to hold the cover in the closed position, said latching system being operable to release the cover allowing the cover to move from the closed position to the open position, the dispenser being characterized in that the frame is connected to the shell by means of at least one deformable connection element of material having lower stiffness than the material(s) of the shell and the frame, said deformable connection element being arranged in such a way that the shell is movable in a limited manner relative to the frame along the sliding direction, the shell being movable with respect to the frame by an extent much smaller than that of the stroke between the open position and the closed position of the cover.