Objective: To assess the agreement between measured height, and height predicted from ulna length using the Malnutrition Universal Screening Tool (MUST) equations, in adult patients admitted to government hospitals in Bloemfontein, South Africa. Design: Descriptive cross-sectional survey. Setting: Medical, surgical, pulmonary, orthopaedic, cardiovascular and general wards at Pelonomi, Universitas and National Hospitals in Bloemfontein. Subjects: All patients between 19 and 60 years, admitted during a two-week period in March 2015, who gave written informed consent, and were able to stand upright and unassisted, were included. Outcome measures: Standing height (via stadiometer; referred to as reference height), weight and ulna length were measured. Predicted height and body mass index (BMI) were calculated from ulna length using MUST equations, and compared with reference height and BMI by 95% confidence intervals (CI) and Bland-Altman analysis.