The invention describes a folding seat (10) for the passenger of a vehicle, in particular but not exclusively a farming machine. The seat (10) comprises a seat plane (12) and a backrest (14) operatively connected together by means of a connection and moving group (16). The connection and moving group (16) is in turn operatively connected to a fixed support structure (18) and is provided with a plurality of hinges (20, 22, 24) that allow the articulation of the seat plane (12) and of the backrest (14), with respect to the support structure (18), about a plurality of different axes. In this way, the seat (10) can be folded, rotated and translated between an open or working position and a closed or rest position with minimal bulk.