The chair has a swiveling back (3, 4) whose rotational axis (D) defines a rear area on the seat (D) with a support (G) for the posterior. A section (32) of the back (3, 4) of the frame extends to the rotational axis (D) where it is connected to the seat support (2) by a single hinge (V). The upholstery is fastened to the seat support (2) in a single piece (8) extending from the seat via the rotational axis (D) to the frame section (30) behind the support for the posterior. The swiveling back consists of a rear support (3) connected by a hinge (V) and a stirrup-shaped tensioner (4) which is secured to said support and which can be inserted into upholstered part (8) of the back. The single-piece upholstery (8) stretches over both the seat and back (3). The rear support (3) has a cross bar (30) to which the upholstery is fastened and from which it extends over the back (3, 4).