OBJECTIVES: To determine the consistency of Medicare coverage of medical devices in national coverage determinations (NCDs) with coverage policies issued by U.S. private payers. METHODS: We used the Tufts Medical Center Medicare National Coverage Determination Database to identify medical devices considered in NCDs from 1999-2013. We categorized each device with respect to its FDA approval pathway and clinical application(s). We compared coverage in the NCD with coverage in equivalent policies issued by the 16 largest private U.S. payers that make their policies publicly available. We categorized each NCD as: equivalent to the private payer policy; more restrictive than the private payer policy; less restrictive than the private payer policy; or, when restrictiveness differed across considered indications, as varied. RESULTS: Medicare considered 47 medical devices through NCDs.  We identified 540 coverage policies issued by private payers for the included devices.  Medicare NCDs were equivalent to the corresponding private payer policies in 51% of cases, more restrictive in 23%, less restrictive in 22%, and varied in 4%.  Independence Blue Cross Group was the payer most often consistent with Medicare (82%), and WellPoint least often consistent (25%).  We found little difference between 510(k) cleared and PMA approved devices, although NCDs were more often less restrictive than the private payer policy for PMA approved devices than for 510(k) cleared devices (31% vs. 17%).  We found few differences among devices by clinical indication. CONCLUSIONS: Medicare coverage of medical devices in NCDs is often inconsistent with coverage by private payers. For patients, this inconsistency means variable access to medical technology, and patients transitioning between health plans may face discontinuity of care.  For industry, inconsistent coverage policy among payers adds uncertainty when designing clinical development programs, and when bringing innovations to market.