Convertible seat which can be located in public places which seat comprises a seat part (1) and a back rest (3) in which case the back rest (3) can be turned in relation to the seat part (1), mechanism (9) in order to convert the seat essentially into a horizontal plane to become a resting surface, equipment in order to secure the items of the user, equipment in order to collect the use charge and equipment in order to cover the seat which has been converted to become at least a resting surface to become at least a partly closed resting space in which case the equipment in order to cover the resting space comprises a covering device (16) with a standard width which can be moved from the back part of the seat forward which covering device comprises control elements (7) which are installed at the both sides of the seat to such height that a needed resting space is formed underneath the covering device (16). The seat comprises an control unit (27) which is adjusted to recognize the payment of the use charge and which is adjusted to allow the moving of the seat into a resting space on the grounds of that in which resting space the space (19) for keeping the items of the user is protected and the mentioned resting space can be closed with the covering device (16) and that the control unit (27) is adjusted move the covering device (16) away from the position which closes the resting space with the help of a regulating unit when the paid utilization time has finished.