A phosphorus-free automatic dishwashing detergent composition comprising: (a) 0.5 to 8 wt % of a first polymer comprising polymerized units of: (i) 60 to 82 wt % (meth)acrylic acid, (ii) 10 to 30 wt % of a monoethylenically unsaturated dicarboxylic acid and (iii) 8 to 25 wt % 2-acrylamido-2-methylpropanesulfonic acid (AMPS); and having Mw from 5,000 to 100,000; (b) 0.5 to 8 wt % of a second polymer comprising polymerized units of: (i) 60 to 95 wt % (meth)acrylic acid, (ii) 5 to 40 wt % 2-acrylamido-2-methylpropanesulfonic acid (AMPS); and having Mw from 5,000 to 100,000; (c) 15 to 50 wt % carbonate, (d) 5 to 50 wt % citrate and (e) 10 to 30 wt % of a bleaching agent.