What Is an NPI Number?

An NPI is a unique 10-digit number that identifies a health care provider in the United States. It is the standard ID on claims and other health care transactions.

The short version

The National Provider Identifier (NPI) was created under HIPAA. Every covered health care provider gets one: doctors, nurses, dentists, therapists, pharmacies, hospitals, clinics and many more. Health plans, billing systems and the government use it to say, without ambiguity, which provider did what.

Key facts

10 digits. The first digit is 1 or 2. The last digit is a check digit that catches most typing mistakes (see how the check digit works).
It carries no meaning. The digits don't encode a state, a specialty or a date. Two doctors in the same office have unrelated numbers.
It's for life. A provider keeps the same NPI when they change jobs, move or switch specialties. What changes is the information on file, not the number.
It isn't a license. An NPI doesn't show that someone is licensed or qualified. It's an identifier. Licenses come from state boards. See NPI vs DEA vs license number.

Who issues it

CMS runs the National Plan and Provider Enumeration System (NPPES), which assigns NPIs and keeps the public registry. Getting one is free. See how to get an NPI.

Two types

Individuals get a Type 1 NPI and organizations get a Type 2. The difference matters on claims.

Sources

Reviewed October 2026. Federal rules and CMS pages change; check them for the latest.

Look one up

Need a number now? Search the registry by NPI, name or organization.