Abstract: The present disclosure is aimed at flame retardant thermoplastic polymer compositions. The flame retardant compositions are advantageously antimony free. The compositions contain an effective flame retarding amount of a combination of one or more bismuth compounds selected from the group consisting of bismuth oxychloride, bismuth oxyfluoride, bismuth oxybromide, bismuth oxyiodide and bismuth oxynitrate and one or more organobromine flame retardants, for instance decabromodiphenyl ether (decabromodiphenyl oxide) or tris[3-bromo-2,2-bis(bromomethyl)propyl]phosphate. The thermoplastic polymer is for instance polypropylene, polyethylene, polystyrene, polypropylene/polyethylene copolymer or thermoplastic olefin. The present formulations advantageously contain no antimony trioxide and achieve V0 according to the UL 94 flammability test.