OBJECTIVES: The objectives of this study are to describe (1) recent trends in TSOAC prescriptions, (2) the source of financing for OACs prescriptions, and (3) geographic variation of provider prescribing patterns for TSOACs among VHA and Medicare dual enrollees. METHODS: We identified patients with a first diagnosis of AF (ICD-9-CM code 427.31 and ICD-10 codes I48.X) in the VHA Corporate Data Warehouse (CDW) between 2012 and 2016. We linked the prescriptions for OACs these patients had in the VHA and in Medicare Part D between 2012 and 2013. RESULTS: We identified 64,763 patients diagnosed with AF who were prescribed OACs during 2012 and 2013. There were 300,659 VHA prescriptions and 106,102 Part D prescriptions during the study period. The proportion of Medicare prescriptions increased from 23.2% in 2012 to 28.0% in 2013. Among the 18 Veterans Integrated Service Networks (VISNs), the proportion of Medicare prescriptions varied between 16.4% (VISN 12, Name) and 46.3% (VISN 4) (median=25.1% ). The proportion of TSOACs increased from 18.0% in 2012 (range 11.5%−32.0% across VISNs) to 25.0% in 2013 (range 16.3%−39.0%). Dabigatran was the most prescribed TSOAC, accounting for 14.8% of all prescriptions in 2012 and 13.2% in 2013. VISN 4 had the highest rate of TSOAC adoption in 2013, with 20.0% of prescriptions for Dabigatran and 16.6% prescriptions for Rivaroxaban. Medicare prescriptions were more likely to be for TSOACs than for warfarin compared to prescriptions within the VHA system. TSOAC prescriptions increased substantially across all VISNs during the study period. CONCLUSIONS: There is substantial geographic variation in TSOAC prescriptions in the VHA. Dual VHA and Medicare use accounts for a significant and increasing proportion of veterans diagnosed with AF. Our results also show significant geographic variation in the adoption of novel anticoagulants within the VHA. Reliance on Medicare Part D has increased during the study period.