The authors present a prospective cost-savings analysis to determine how the use of portable coagulometers in the home health setting affects medical expenditure. Thirty-five elderly patients (mean age 67 years) receiving cardiac home health care and long-term oral anticoagulation were evaluated with paired measurements of the international normalized ratio by both a traditional, laboratory-based prothrombin time and a point-of-care coagulometer (CoaguChek, Roche Diagnostics, Basel, Switzerland). Costs for materials, procedures, transportation, and labor were summed for both methods, and it was found that cost of international normalized ratio determination by the portable coagulometer was significantly less than the traditional method ($6.85 vs. $17.30; p<0.001). The authors conclude that by saving on the costs of transporting and processing traditional international normalized ratio specimens, use of point-of-care coagulometers by home health nurses could reduce medical expenditure. The cost savings and potential improvement in quality of care argue for equipping home health nurses with portable coagulometers.