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Background: Patients receiving warfarin who spend a lower proportion of time in therapeutic international normalized ratio (INR) range (TTR) have a higher risk of both bleeding complications and thromboembolic events. Using warfarin dosing algorithms is one intervention associated with improved INR stability. Objective: To determine the feasibility of an individualized warfarin dosing algorithm (Fearon Algorithm) under anticoagulation management service (AMS) care and compare measures of INR control using the algorithm with standard care. Methods: A pre/post intervention feasibility study consisting of the 12 months prior to patient enrollment (pre-study phase) and 6 months in which patients used the Fearon Algorithm under the supervision of an AMS pharmacist (AMS phase). The primary study outcome was the change in individual TTR. Results: A total of 30 patients were enrolled in the study, 26 (87%) of whom successfully completed the AMS study phase using the Fearon Algorithm. Median corrected individual TTR increased significantly from 53% (IQR: 39%, 64%) during the year prior to enrollment to 63% (IQR: 57%, 73%) during the AMS phase (p < 0.01) The uncorrected TTR also increased significantly from 52% (IQR: 39%, 64%) to 61% (IQR: 57%, 72%) (p < 0.01). The Fearon Algorithm specified a smaller warfarin tablet strength in half the patients. Conclusion: The Fearon Algorithm is feasible for an AMS to implement in patients receiving long-term warfarin therapy and appears to improve TTR.