Abstract: Re-use and extended uses of a paint bucket of conventional form and proportions are promoted by disposable thin internal fluid-tight liners vacuum-formed from relatively thick thermoplastic sheet material; each such liner has exceedingly thin bottom and side walls but is self-sustaining in shape because of circular stiffening by a thick upper rim shaped to snap-lock with and overhang the bucket rim and also because of longitudinal stiffening imparted by several inwardly-projecting hemicylindrical ribs disposed along the side walls where they will serve as vents facilitating insertion and removal of the close-fitting bucket liner.