Thermoformable films that contain a blend and/or composite structure containing an ethylene/vinyl or vinylidene aromatic polymer or an alpha-olefin/vinyl or vinylidene aromatic polymer, such as an ethylene/styrene interpolymer, a vinyl or vinylidene aromatic homo- or copolymer, such as polystyrene, and, optionally, an alpha-olefin homo- or copolymer serve as effective carrier layers for heat transfer foils.