Widespread adoption of electronic medical record (EMR) systems is increasing. EMR implementation can be costly and typically requires workflow redesign. To our knowledge, no studies to date have examined the impact of EMR implementation using advanced cost accounting methods or the impact of its implementation on orthopaedic surgeons in an outpatient setting. Time-driven activity-based costing (TD-ABC) was used to evaluate the effect of EMR implementation in an outpatient adult reconstruction clinic. One hundred and forty-three patients were prospectively timed throughout their visit to clinics, before implementation of a hospital system-wide EMR system and then again 2 months, 6 months, and 2 years after implementation. Data were analyzed to investigate the effects of EMR implementation on labor cost and provider time. Using TD-ABC, we observed the EMR implementation learning period, returning to pre-introduction efficiency at 6 months. Cost increases because of increased certified medical assistant time spent with patients and physician time on documentation were offset by less patient-physician interaction. Health-care systems and policymakers should be aware that the length of the implementation period is approximately 6 months and that implementation may alter the time that providers spend with patients.