A vehicle seat, comprising: a lower frame, intended to be connected to the floor of a vehicle, having: a base, intended to be connected to the floor of the vehicle, and a seating portion frame, comprising at least two seating places to accommodate at least two users, a first backrest pivotally hinged to the base, a second backrest pivotally hinged to the base, wherein the seat further comprises a connection system connecting the first backrest to the seating portion frame, configured so that the pivoting of the first backrest relative to the base causes the simultaneous movement of the seating portion frame relative to the base in the longitudinal direction and the vertical direction of the seat, in the two pivoting directions of the first backrest relative to the base.