OBJECTIVES: Since their introduction to the US market in 2010, non-Vitamin K oral anticoagulants (NOACs) have sought to address the issues of not only efficacy, but also safety, ease of use, and patient compliance. However, little is known about the trends in the utilization of these medications after hip or knee replacement surgery. In this study, we analyzed changes in prescription volumes for oral anticoagulants since the introduction of NOACs in United States in major orthopedic surgery patients. METHODS: Using Truven Health MarketScan data, we analyzed prescription volumes for warfarin, dabigatran, rivaroxaban, and apixaban from January 2010 to September 2016 in patients undergoing total knee or hip replacement surgery. The total prescription volume was calculated quarterly and included new fills and refills for these medications. RESULTS: The overall volume of oral anticoagulant prescriptions in hip and knee replacement surgery patients in United States has increased annually since 2010. Since the availability of the NOACs, the proportion of total oral anticoagulant prescriptions attributable to warfarin in these patients has steadily decreased, from 99% in 2010 to 72% by September 2016. The largest increase in NOAC prescribing occurred between 2012 and 2014, which corresponds to the timeframe when rivaroxaban was first listed on most formularies. By September 2016, rivaroxaban held a 19% share of the oral anticoagulant market in orthopedics, whereas dabigatran and apixaban together accounted for approximately 9%. CONCLUSIONS: Since their approval, the NOACs have represented a growing share of total OAC prescriptions in orthopedic surgery patients in United States. This trend is expected to continue because the NOACs are given preference over warfarin in guidelines on venous thromboembolism prevention in major orthopedic surgery patients. An understanding of the current prescribing patterns will help to influence health policy and reimbursement strategies.