Abstract: The invention relates to a a vehicular seat booster cushion (1) for a permanent vehicle seat (6) and being provided with a first sitting surface (2) for accommodating an occupant (7) and a first resting surface (12; 14) adapted to be positioned on said seat (6) in a first position of said booster cushion (1), said first sitting surface (2) extending generally along a plane which is at a first distance (d1) from said first resting surface (12; 14). The booster cushion (1) is also provided with a second sitting surface (3) for accommodating an occupant and a second resting surface (13; 15) adapted to be positioned on said seat (6) in a second position of said booster cushion (1), said second sitting surface (3) extending generally along a plane which is at a second distance (d2) from said second resting surface (13; 15), and wherein said first distance (d1) and said second distance (d2) are different, so as to be used by occupants (7) of different height.