BACKGROUND: Current guidelines recommend a minimum of 3 months’ anticoagulation (AC) following venous thromboembolism (VTE). The decision to prolong treatment depends on clinicians’ perception of benefit-risk, patient characteristics, and preferences. As evidence is limited for the optimal duration of therapy, considerable variability exists in routine care. OBJECTIVES: To describe the duration of AC following VTE in clinical practice in England and identify factors associated with longer duration. METHODS: Retrospective study of all VTE events between 1 April 2008 and 31 March 2012 in linked Clinical Practice Research Datalink/Hospital Episode Statistics databases. We defined VTEs by Read or ICD-10 codes with anticoagulant prescription within 45 days after VTE or hospital discharge. We used multivariate Cox regression to identify factors associated with AC duration (event=end of AC). RESULTS: Of 11,353 VTEs, 45.0% were PEs and 48.5% were in men. Mean patient age was 63.9 years. Median AC duration was 219 days. In the Cox model, previous VTE was strongly associated with increased AC duration (HR: 0.46 [95%CI 0.42-0.50]). Other factors associated with longer AC duration were age >40 (vs ≤40, 41-64: 0.82 [0.76-0.89]; 65-79: 0.74 [0.68-0.80]; ≥80: 0.82 [0.75-0.90]), PE (vs DVT, 0.71 [0.68-0.75]), active cancer (vs unprovoked VTE, 0.86 [0.80-0.92]), hospitalisation (vs no hospitalisation, leading to hospitalisation: 0.81 [0.77-0.85], during hospitalisation: 0.72 [0.66-0.79]), and history of systemic arterial thromboembolism (0.72 [0.56-0.91]). Other factors retained by the Cox model were gender, body mass index, geographic region, and previous major bleeding. CONCLUSIONS: In routine practice in England, most patients received more than 6 months of AC therapy after VTE. Factors associated with prolonged AC corresponded to risk factors commonly thought to increase VTE recurrence. Consensus concerning the optimal length of AC treatment following acute VTE (beyond 3 months) may help to minimize variability in patient care in the future.