Question: I am training for a position in billing in a practice and am trying to get the hang of some different acronyms. Could you please help me understand the difference between NPI and PTAN? Arkansas Subscriber Answer: NPI stands for National Provider Identifier; PTAN stands for Provider Transaction Access Number. The NPI is a 10-digit “intelligence-free” numeric identifier that does not showcase any information about a provider’s specialty or location. Under HIPAA provisions, covered healthcare providers, as well as all health plans and healthcare clearinghouses — and any other necessary entity — have to use the NPI on administrative and financial transactions, says the Medicare Learning Network (MLN). “You should note that individual health care providers (including physicians who are sole proprietors) may obtain only one NPI for themselves (Entity Type 1 Individual). Incorporated individuals should obtain one NPI for themselves (Entity Type 1 Individual) if they are health care providers and an additional NPI(s) for their corporation(s) (Entity Type 2 Organization). Organizations that render health care or furnish health care supplies may obtain NPIs (Entity Type 2 Organization) for their organizations and their subparts (if applicable),” MLN notes. The PTAN is specific to Medicare, is assigned by a provider’s Medicare Administrative Contractor (MAC), and is used to authenticate the provider’s use of some online tools available through their respective MAC. Each provider must have a single NPI, but may have one or more PTAN(s). “If the provider has relationships with one or more medical groups or practices or with multiple Medicare contractors, separate PTANS are generally assigned,” MLN explains. Important tip: “While only the National Provider Identifier (NPI) is submitted on claims, the PTAN is a critical number directly linked to a provider or supplier’s NPI. A PTAN’s use should generally be limited to a provider’s communication with their MAC,” says MAC Noridian.