A suspension mat (14) for a vehicle seat comprises one or more suspension springs (16) for supporting a cushion (28), a support plate (18) attached to the one or more suspension springs, a mobile plate (34) coupled with the support plate, a flat spring (26) arranged between the support plate and the mobile plate and a switch element. The mobile plate is arranged movable between a first and a second position relative to the support plate. The flat spring biases the mobile plate toward the first position. The switch element is located between the support plate and the flat spring, in such a way that when the mobile plate moves against a bias of the flat spring toward the second position, the flat spring presses and actuates the switch element. The flat spring may e.g. comprise a washer spring, a plate spring, a dome-shaped flat spring and/or a cantilever flat spring.