What is an NPI?
A National Provider Identifier (NPI) is a unique ten-digit number that the Centers for Medicare & Medicaid Services (CMS) assigns to health care providers in the United States. It identifies the provider in standard electronic health care transactions such as claims and eligibility checks.
Why NPIs exist
The Health Insurance Portability and Accountability Act of 1996 (HIPAA) required a standard unique identifier for health care providers. CMS adopted the NPI as that standard and began assigning numbers in 2005 through the National Plan and Provider Enumeration System (NPPES). Providers covered by HIPAA must use their NPI in standard transactions, and health plans and clearinghouses must accept it. CMS describes the standard on its National Provider Identifier Standard page.
Two entity types
- Type 1 NPIs belong to individual people who provide health care, such as physicians, nurses, dentists, pharmacists, and therapists. See individual providers.
- Type 2 NPIs belong to organizations, such as hospitals, group practices, clinics, pharmacies, laboratories, and nursing facilities. See organization providers.
A person who owns a practice may hold a Type 1 NPI for themselves and a Type 2 NPI for the business.
Format and check digit
An NPI is always ten digits and carries no embedded information about the provider. The tenth digit is a check digit computed with the Luhn formula after prefixing the number with 80840, the identifier for the United States health industry. The check catches most single-digit typing errors: if a number fails it, one digit is probably wrong. The NPI lookup on this site applies the check in your browser.
What information is public
When providers apply for an NPI they supply identifying and location information. CMS releases the parts of the record that are disclosable under the Freedom of Information Act in the NPPES data dissemination files and through the NPPES NPI Registry. The public record includes the provider's name, entity type, practice and mailing addresses, telephone numbers, taxonomy codes, enumeration date, and last-update date. Social Security numbers, dates of birth, and similar personal data are not released.
What an NPI is not
An NPI is an identifier, not a credential. Holding an active NPI does not mean a provider is licensed in a state, board certified, enrolled in Medicare or another plan, employed by a particular organization, or currently practicing. Licensure is verified with state boards; plan participation with the plan; and the rest with the provider.
How to look up or update an NPI
- To find or verify a current record, use the official NPPES NPI Registry, which is updated continuously.
- To browse a fixed snapshot of selected records by state and city, use this site's directories from the home page; each page states its data date.
- Providers apply for an NPI and update their record through the NPPES portal. CMS requires changes to be reported within 30 days.