Survival and causes of death were analyzed among 163 patients with hemochromatosis diagnosed between 1959 and 1983. Mean followup was 10.5 +/- 5.6 years (+/- SD). Cumulative survival was 76% at 10 years and 49% at 20 years. Life expectancy was reduced in patients who presented with cirrhosis or diabetes compared to patients who presented without these complications at the time of diagnosis. Patients who could be depleted of iron during the first 18 months of venesection therapy had a markedly better prognosis compared to those patients who could not be depleted during this time period, probably due to greater amounts of excessive iron. Prognosis was not influenced by sex. Patients without cirrhosis or diabetes had a life expectancy that was virtually identical to that of an age-matched normal population. Analysis of the causes of death in 53 patients showed that liver cancer (n = 16) was 219 times more frequent, cardiomyopathy (n = 3) was 306 times more frequent, liver cirrhosis (n = 10) was 13 times more frequent, and diabetes mellitus (n = 3) was seven times more frequent compared to death rates expected for an age-matched normal population. The risk of death from other causes, including extrahepatic cancer (n = 7), did not differ from rates expected. Thus, patients with hemochromatosis diagnosed in a precirrhotic stage and treated by venesection have a normal life expectancy. Cirrhotic patients had a shortened life expectancy and a high risk of death from liver cancer even when complete iron depletion has been achieved.