<P> A National Provider Identifier or NPI is a unique 10 - digit identification number issued to health care providers in the United States by the Centers for Medicare and Medicaid Services (CMS). The NPI has replaced the unique physician identification number (UPIN) as the required identifier for Medicare services, and is used by other payers, including commercial healthcare insurers . The transition to the NPI was mandated as part of the Administrative Simplifications portion of the Health Insurance Portability and Accountability Act of 1996 (HIPAA), and CMS began issuing NPIs in October 2006 . </P> <P> HIPAA covered entities such as providers completing electronic transactions, healthcare clearinghouses, and large health plans were required by regulation to use only the NPI to identify covered healthcare providers by May 23, 2007 . CMS subsequently announced that as of May 23, 2008, CMS will not impose penalties on covered entities that deploy contingency plans to facilitate the compliance of their trading partners (e.g., those healthcare providers who bill them). The posted guidance document can be used by covered entities to design and implement a contingency plan . Details are contained in a CMS document entitled, "Guidance on Compliance with the HIPAA National Provider Identifier (NPI) Rule ." Small health plans have one additional year to comply . </P>

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