<p>The long-term consequences of sepsis, including mortality and morbidity among survivors, are insufficiently understood. This nationwide matched cohort study investigated the association between presumed community-acquired critical sepsis (PCACS)and long-term mortality, the morbidity of burden before and after ICU admission, and causes of death. Patients admitted to Swedish ICUs for PCACS over a ten-year period (<i>n</i> = 10,072) were matched 1:5 with population controls (<i>n</i> = 50,180). Data on demographics, comorbidities, education, income, and causes of death were collected. Conditional Cox regression was used to assess long-term mortality. Patients with sepsis exhibited a progressive increase in morbidity during the five years preceding ICU admission, which further escalated in the year following discharge. Sepsis was associated with excess mortality up to three years post-admission. Among one-year survivors, sepsis remained independently associated with increased mortality between years one and three, even after adjusting for prior morbidity, indicating persistent long-term effects not fully explained by diagnosed conditions. Early deaths were primarily due to infections and cancer, while later deaths were dominated by cancer and circulatory diseases. These findings highlight the sustained impact of sepsis on survivors, underscoring the need for long-term follow-up and targeted interventions to mitigate post-septic morbidity and mortality.</p>