To assess excess mortality from chronic disease in the United States, state age-adjusted combined mortality rates for nine chronic diseases in 1986 were compared with three "minimum" rates--two calculated from rates actually achieved in states and a third estimated as the mortality remaining after elimination of one risk factor for each disease. Hawaii had the lowest mortality rate of combined diseases (305/100,000); state excesses ranged from 0% to 37%. The sum of lowest disease-specific rates in any state was 284 per 100,000, indicating excesses of between 7% and 41%. A minimum mortality rate of 224 per 100,000 was estimated to result from elimination of one risk factor for each of the nine diseases, indicating state excesses from 26% to 54%, or 524,000 US deaths. Reduction of US mortality from the nine diseases to the risk factor--eliminated rate is estimated to be associated with an increased life expectancy at birth of 4 years.