Currently available estimates of outcomes following colon resection in elderly patients with colon cancer are based on series collected at academic medical centers. We used Medicare Part A claims and enrollment records of a 5% nationally random sample of elderly Medicare beneficiaries from 1983 to 1985 to estimate how patient age and sex affected perioperative mortality and 1- and 2-year survival rates among elderly patients undergoing a colon resection procedure for colon cancer. Among the 5,586 individuals in our data set, the overall perioperative mortality rate was 5.0%, ranging from 3.3% in beneficiaries 66 to 69 years of age to 9.3% in those 85 years of age and older. Men had a 31% higher perioperative mortality rate than women (5.8% versus 4.4%, p < 0.05). The overall postoperative survival rates at 1 and 2 years were 72% and 63%, respectively, decreasing with increasing age, but were similar in men and women. This analysis provides age- and sex-specific estimates of outcomes following surgery for elderly patients with colon cancer that are more precise and have more potential for generalization than those that were available previously.