A mounting arrangement for attaching a toilet seat and cover to a toilet bowl is disclosed which facilitates installation without the use of conventional hand tools. The arrangement includes a base having a hinge post for hingedly connecting the seat and cover thereto. The base further includes a downwardly depending stem having a longitudinal bore which is adapted to be positioned within the mounting hole on the toilet bowl. A fastener assembly is provided which includes a bolt positioned within the longitudinal bore of the stem which may be readily rotated by hand. An expandable nut is threaded to the lower end of the bolt, with the entire mounting arrangement being insertable into the mounting hole of the bowl from the seat side thereof. As the bolt is rotated to draw the nut toward the base of the arrangement, at least one of the stem and expandable nut are urged into engagement with the periphery of the mounting hole, thereby providing securement of the mounting arrangement to the toilet bowl, while accommodating use of the mounting arrangement on toilet bowls having mounting holes of varying diameters.