A thermoplastic molding composition characterized by its flame retardance and impact strength is disclosed. The composition contains A) 70 to 99 parts by weight of aromatic poly(ester) carbonate B) 1 to 30 parts by weight of polyalkylene terephthalate, the total weight of A) and B) being 100 parts resin, and C) 1 to 20 parts per hundred parts resin (phr) of graft (co)polymer having a core-shell morphology, including a grafted shell that contains polymerized alkyl(meth)acrylate and a composite rubber core that contains interpenetrated and inseparable polyorganosiloxane and poly(meth)alkyl acrylate components, D) 2 to 20 phr of a phosphorous-containing compound, and E) 0.1 to 2 part by weight of fluorinated polyolefin.