To determine the timing of symptomatic venous thromboemboli (VTE) in patients sustaining a pelvic and/or acetabular fracture. Secondly, to evaluate for any factors that may influence this timing. A retrospective cohort of 47 patients with acetabular and/or pelvic ring injuries who developed VTEs at a single academic level I trauma center were identified from 2012 to 2018. The chronology of VTE diagnosis in relation to date of injury, initial surgery, final surgery, and date of discharge was evaluated. Patients who developed VTEs were then evaluated based on known risk factors for VTE to determine if any of these affected timing. Symptomatic VTEs were diagnosed in 3.8% of patients with pelvic and/or acetabular fractures. In patients who developed a thromboembolism, diagnosis occurred on average 21.5 (± 19.2), 20.7 (± 19.9), 9.8 (± 23.4), and 4.3 (± 27.6) days after injury, index procedure, final procedure, and date of discharge. 25% of patients developed VTE more than 4weeks after their initial injury. No known risk factors effected the timing of VTE. The 2015 OTA expert panel recommends 4weeks of anticoagulation for orthopedic trauma patients at high risk of VTE, which may be too short a duration. In our cohort, 25% of VTEs occurred greater than 4weeks after injury. Additional research is needed to clarify the exact duration of anticoagulation after pelvic and acetabular fractures; however, surgeons may want to consider anticoagulating patients for greater than 4weeks. Level III-retrospective cohort.