Abstract: A litter box or container holds granulated litter material for an animal's use and is configurable between the shape of a rectanguloid closed container confining the litter material and an open bin or tray in which the litter material is disposed for use. An arrangement of deformable and foldable wall portions in the container permits reconfiguration without removal of the litter material, permitting easy transportation, use and disposal as a unit. The container is formed of sheet material containing fold lines. The fold lines alternately define within the sheet material a closed package that has an essentially square shaped cross section along at least one axis of said cavity and an open tray, the tray having upstanding continuous side walls defining an open cavity, with the volume of the tray cavity being at least twice as large as that of the alternate configuration as a packaage. Litter material is disposed within said container and is carried between the two configurations.