Objective To determine the effect of sex on sepsis-related ICU admission and survival for up to 3-years. Methods Retrospective cohort study of adults admitted to Australian ICUs between 2018 and 2020. Men and women with a primary diagnosis of sepsis were included. The primary outcome of time to death for up to 3-years was examined using Kaplan Meier plots. Secondary outcomes included the duration of ICU and hospital stay. Results Of 523,576 admissions, there were 63,039 (12.0%) sepsis-related ICU admissions. Of these, there were 50,956 patients (43.4% women) with 3-year survival data. Men were older (mean age 66.5 vs 63.6 years), more commonly received mechanical ventilation (27.4% vs 24.7%) and renal replacement therapy (8.2% vs 6.8%) and had worse survival (Hazard Ratio [HR] 1.11; 95% Confidence Interval [CI] 1.07 to 1.14, P<0.001) compared to women. The duration of hospital and ICU stay was longer for men, compared to women (median hospital stay, 9.8 vs 9.4 days; p<0.001 and ICU stay, 2.7 vs 2.6 days; p<0.001). Conclusion Men are more likely to be admitted to ICU with sepsis and have worse survival for up to 3-years. Understanding causal mechanisms of sex differences may facilitate the development of targeted sepsis strategies.