A storage device for a franking machine, which storage device comprises: a receptacle for receiving mailpieces ejected one-by-one by the franking machine; a longitudinal referencing wall extending over a longitudinal edge of the receptacle and against which the mailpieces rebound before they accumulate on the receptacle; and a vertical back wall extending along a side edge of the receptacle and that the mailpieces hit before they rebound against the longitudinal referencing wall; the vertical back wall forming an angle β with a perpendicular to the longitudinal referencing wall; and the receptacle being inclined relative to the horizontal and towards the longitudinal referencing wall at an angle φ so that the angle α between the receptacle and the longitudinal referencing wall forms an acute angle.