Introduction: Venous thromboembolism (VTE) is a serious, frequent, and preventable medical complication in hospitalized patients. Although the efficacy of prophylaxis (pharmacological and/or mechanical) has been demonstrated, compliance with prophylaxis is poor at international and national levels. Aim: To determine the indication and use of pharmacological thromboprophylaxis in hospitalized patients in Uruguay. Methods: An observational, descriptive, cross-sectional, multicentre study involving 31 nationwide healthcare facilities was conducted. Baseline characteristics associated with hospital admission, the percentage of the population with an indication for thromboprophylaxis, and the percentage of patients receiving pharmacological thromboprophylaxis were assessed. The VTE risk was determined using the Padua score for medical patients; the Caprini score for surgical patients; the Royal College of Obstetricians and Gynaecologists (RCOG) guidelines for pregnant-postpartum patients. Results: 1925 patients were included, representing 26% of hospitalized patients in Uruguay. 71.9% of all patients were at risk of VTE. Of all patients at risk of VTE, 58.6% received pharmacological thromboprophylaxis. The reasons for not receiving thromboprophylaxis were prescribing omissions in 16.1% of cases, contraindication in 15.9% and 9.4% of patients were already anticoagulated for other reasons. Overall, just 68% of patients were "protected" against VTE. Recommendations of major thromboprophylaxis guidelines were followed in 70.1% of patients at risk. Conclusions: Despite the progress made in adherence to thromboprophylaxis indications, nonadherence remains a problem, affecting one in six patients at risk of VTE in Uruguay.