Abstract Background The number of patients undergoing autologous haematopoietic cell transplant (HCT) is growing, but little is known about the factors that predict adverse outcomes. Low muscle mass and obesity are associated with disability and premature mortality in individuals with non‐malignant diseases and may predict outcomes after autologous HCT. Methods This was a retrospective cohort study of 320 patients who underwent autologous HCT for Hodgkin or non‐Hodgkin lymphoma between 2009 and 2014. Sarcopenia {skeletal muscle index male: