A metallized film and a process for making the film are disclosed. In general, the metallized film includes a polymeric film layer that is coated with a polyester coating composition. A metal layer is then formed on top of the polyester coating. The polyester coating acts as a tie layer between the metal layer and the underlying film. The polyester film composition may be formed from, in one embodiment, isophthalic acid, a sulfomonomer, and 2-methyl 1,3-propane diol. The above diol has been found to improve adhesion between the metal layer and the polymeric film layer.