A wheelchair has a platform assembly that includes a slide-out tray, a flexible cover, a toilet basin, and a storage pouch. The toilet basin is equipped with a waste liner and is capable of being removed from the slide-out tray. The bottom of the assembly has guide rails that enable the flexible cover to cover the toilet basin when it is inserted into the slide-out tray. The pouch, which is located on a front of the toilet seat can store supplies such as liners and deodorizers, as well as to conceal the toilet basin.