A heat-sealable polymeric film includes a substrate layer of polymeric material having on a surface thereof a heat-sealable coating layer. The layer includes a copolyester having a degree of crystallinity of at least 5%, and is less than 8 μm in thickness. The copolyester consists essentially of repeat units of one or more aromatic dicarboxylic acids, one or more aliphatic dicarboxylic acids, and a stoichiometric amount of a glycol component consisting of one or more glycols selected from the group consisting of aliphatic glycols and cycloaliphatic glycols.