Abstract: A chemical mechanical polishing composition for polishing a substrate having a tungsten layer includes a water based liquid carrier, abrasive particles dispersed in the liquid carrier, an iron containing accelerator, and a cationic polymer having an amino acid monomer. A method for chemical mechanical polishing a substrate including a tungsten layer includes contacting the substrate with the above-described polishing composition, moving the polishing composition relative to the substrate, and abrading the substrate to remove a portion of the tungsten from the substrate and thereby polish the substrate.