Purpose To determine the impact of uninterrupted use of warfarin on hand and wrist surgery. Methods This single-center, prospective cohort trial enrolled adult patients undergoing hand and wrist surgery. Between May 2009 and August 2014, 47 surgical patients receiving uninterrupted warfarin (50 procedures) were enrolled and matched as a group by age and procedure type to 48 surgical patients (50 procedures) who were not prescribed warfarin. Complications, defined as bleeding, infection, or wound dehiscence requiring reoperation, were recorded for each group. Surgical outcome measures were composed of objective findings affected by surgical site bleeding (ie, ecchymosis extent, hematoma presence, 2-point discrimination) and standardized patient-rated assessments (Quick-Disabilities of the Arm, Shoulder, and Hand, and visual analog scales: pain and swelling). We collected data preoperatively and at 2 and 4 weeks postoperatively. Statistical analyses contrasted complications and outcomes data between patient groups. Results One procedure (2%; 95% confidence interval, 0% to 11%) in a patient taking warfarin was complicated by hematoma requiring reoperation resulting from an elevated postoperative international normalized ratio of 5.4. There were no complications among controls (0%; 95% confidence interval, 0% to 7%). At 2 weeks postoperatively, patients receiving warfarin more frequently had hematomas (28% vs 10%) and demonstrated a greater extent of ecchymosis from the surgical incision (50 vs 19 mm). At 4 weeks, no differences existed in hematoma presence or extent of ecchymosis between groups. The incidence of transiently elevated 2-point discrimination was not different between groups (10% warfarin; 6% controls). Visual analog scores for pain and swelling were not significantly different between groups at any time. Differences in Quick-Disabilities of the Arm, Shoulder, and Hand scores between groups did not exceed a minimal clinically important difference. Conclusions Uninterrupted use of warfarin in patients undergoing surgery of the hand and wrist was associated with an infrequent risk of bleeding complication requiring reoperation. Increased rates of hematoma and ecchymosis in patients taking warfarin normalized by 4 weeks postoperatively.