A washing machine comprising: • an outer casing; • a treatment chamber for receiving a load to be washed; • a pump unit for discharging water from said treatment chamber; • a filter assembly interposed between said treatment chamber and said pump unit for filtering washing/rinsing liquid discharged from said treatment chamber, said filter assembly comprising a filter element and a filter body defining a seat for removably housing said filter element; wherein washing machine comprises a connection interface into which an opening is defined and through which said filter element can be inserted into/removed from said filter body; said filter assembly further comprising: • a connecting device for connecting said filter body to said connection interface such that said seat of said filter body is aligned with said opening; wherein said connecting device comprises: - a guide member and a respective engagement portion that is shaped for matching with said guide member such that said filter body and said connection interface are coupled together at least along an axis corresponding to the removal and insertion direction of said filter element in said seat, - an automatic fastening locking element, automatically fastening said engagement portion to said guide member when said engagement portion reaches a predetermined fastening position into said guide member, so as to prevent movements of said engagement portion with respect to said guide member at least along a withdrawal direction of said engagement portion from said guide member, wherein said automatic fastening locking element is a snap-fit locking element, wherein said connecting device further comprising a resilient stopping element which is urged away by said snap-fit locking element until said engagement portion matches with said guide member at least up to said predetermined fastening position, said resilient stopping element abutting against an abutment surface of said snap-fit locking element, preventing the movement of said engagement portion with respect to said guide member, when said engagement portion is moved back from said predetermined fastening position, characterized in that said resilient stopping element is formed on a resilient flap against which the snap-fit locking element urges before reaching a predetermined fastening position as defined by the engagement portion reaching said predetermined fastening position into said guide member, said flap developing along a surface which is tilted with respect to a path followed by an outermost portion of said snap-fit locking element as said engagement portion travels into said guide member, such that said flap is gradually deformed by the urging of said snap-fit locking element until the snap-fit locking element passes the flap and the flap then returns into its non-deformed condition to thereby enable the abutment surface of the locking element to abut against the resilient stopping element on the flap. • an outer casing; • a treatment chamber for receiving a load to be washed; • a pump unit for discharging water from said treatment chamber; • a filter assembly interposed between said treatment chamber and said pump unit for filtering washing/rinsing liquid discharged from said treatment chamber, said filter assembly comprising a filter element and a filter body defining a seat for removably housing said filter element; • a connecting device for connecting said filter body to said connection interface such that said seat of said filter body is aligned with said opening; - a guide member and a respective engagement portion that is shaped for matching with said guide member such that said filter body and said connection interface are coupled together at least along an axis corresponding to the removal and insertion direction of said filter element in said seat, - an automatic fastening locking element, automatically fastening said engagement portion to said guide member when said engagement portion reaches a predetermined fastening position into said guide member, so as to prevent movements of said engagement portion with respect to said guide member at least along a withdrawal direction of said engagement portion from said guide member, wherein said automatic fastening locking element is a snap-fit locking element, wherein said connecting device further comprising a resilient stopping element which is urged away by said snap-fit locking element until said engagement portion matches with said guide member at least up to said predetermined fastening position, said resilient stopping element abutting against an abutment surface of said snap-fit locking element, preventing the movement of said engagement portion with respect to said guide member, when said engagement portion is moved back from said predetermined fastening position, characterized in that said resilient stopping element is formed on a resilient flap against which the snap-fit locking element urges before reaching a predetermined fastening position as defined by the engagement portion reaching said predetermined fastening position into said guide member, said flap developing along a surface which is tilted with respect to a path followed by an outermost portion of said snap-fit locking element as said engagement portion travels into said guide member, such that said flap is gradually deformed by the urging of said snap-fit locking element until the snap-fit locking element passes the flap and the flap then returns into its non-deformed condition to thereby enable the abutment surface of the locking element to abut against the resilient stopping element on the flap.