Toilet arrangement, which includes a gravity toilet bowl (1) provided with a water trap (11) and an outlet (12). The arrangement further includes a water valve (5), a flush water tank (4), and a flush valve (6) arranged between the flush water tank (4) and the toilet bowl (1), and an activating means (8) for activating a flushing sequence. In order to allow for the use of a standard gravity toilet bowl in connection with a vacuum sewage system, the toilet arrangement comprises an adapter (13) which is arranged between the gravity toilet bowl (1) and a discharge valve (2) connected to a vacuum sewer piping (3). A control mechanism (7) is connected to the vacuum sewer piping (3), the discharge valve (2), the water valve (5) and the flush valve (6), whereby the control mechanism (7) is arranged to be activated by means of the activating means (8).