ObjectiveTo assess inequities in mortality by race and sex for eight common surgical procedures (elective and non-elective) across specialties in the United States.DesignRetrospective cohort study.SettingUS, 2016-18.Participants1 868 036 Black and White Medicare beneficiaries aged 65-99 years undergoing one of eight common surgeries: repair of abdominal aortic aneurysm, appendectomy, cholecystectomy, colectomy, coronary artery bypass surgery, hip replacement, knee replacement, and lung resection.Main outcome measureThe main outcome measure was 30 day mortality, defined as death during hospital admission or within 30 days of the surgical procedure.ResultsPostoperative mortality overall was higher in Black men (1698 deaths, adjusted mortality rate 3.05%, 95% confidence interval 2.85% to 3.24%) compared with White men (21 833 deaths, 2.69%, 2.65% to 2.73%), White women (21 847 deaths, 2.38%, 2.35% to 2.41%), and Black women (1631 deaths, 2.18%, 2.04% to 2.31%), after adjusting for potential confounders. A similar pattern was found for elective surgeries, with Black men showing a higher adjusted mortality (393 deaths, 1.30%, 1.14% to 1.46%) compared with White men (5650 deaths, 0.85%, 0.83% to 0.88%), White women (4615 deaths, 0.82%, 0.80% to 0.84%), and Black women (359 deaths, 0.79%, 0.70% to 0.88%). This 0.45 percentage point difference implies that mortality after elective procedures was 50% higher in Black men compared with White men. For non-elective surgeries, however, mortality did not differ between Black men and White men (1305 deaths, 6.69%, 6.26% to 7.11%; and 16 183 deaths, 7.03%, 6.92% to 7.14%, respectively), although mortality was lower for White women and Black women (17 232 deaths, 6.12%, 6.02% to 6.21%; and 1272 deaths, 5.29%, 4.93% to 5.64%, respectively). These differences in mortality appeared within seven days after surgery and persisted for up to 60 days after surgery.ConclusionsPostoperative mortality overall was higher among Black men compared with White men, White women, and Black women. These findings highlight the need to understand better the unique challenges Black men who require surgery face.