Disclosed is an improved weatherable thermoplastic composition. The composition is comprised of a copolymer of an alkyl acrylate or alkyl methacrylate and (methyl)methacrylate and a multi-stage, sequentially-polymerized impact modifier polymer. The copolymer is characterized by greater than 15 weight percent alkyl acrylate content. The multi-stage, sequentially-polymerized impact modifier is characterized by an elastomer stage, which is 55 percent by weight or greater of the impact modifier composition and is minimally crosslinked. The thermoplastic composition can be used in a wide range of film, sheet, or molded applications.