What Is the NPI Registry? Complete Guide

The NPI Registry is a public federal database of every US healthcare provider, maintained by the Centers for Medicare and Medicaid Services (CMS). It assigns each provider a unique 10-digit National Provider Identifier and lists name, primary practice address, specialty taxonomy code, and enrollment status. The registry was created under HIPAA in 2004 and is the authoritative source of US healthcare provider identity. The Doctor Directory sources every physician profile from the NPI Registry, which is why every US MD and DO has a placeholder profile ready to claim.

What the NPI Registry Contains

FieldExamplePublic?
NPI number (10 digits)1234567890Yes
Provider nameDr. Jane SmithYes
Provider typeIndividual (Type 1) or Organization (Type 2)Yes
Primary practice address123 Main St, Miami, FL 33101Yes
Mailing addressSame or different from practiceYes
Specialty taxonomy code207R00000X (Internal Medicine)Yes
Enumeration date2015-03-14Yes
Status (Active / Deactivated)ActiveYes

What the NPI Registry does NOT contain:

How to Search the NPI Registry

  1. Visit the official CMS search at npiregistry.cms.hhs.gov
  2. Enter first name, last name, city, state, or NPI number
  3. Results show the provider name, NPI, primary practice address, and specialty
  4. Click any result for the full record

You can also search from The Doctor Directory - our /find-a-doctor page reads from the NPI Registry, layered with patient reviews and moderated content. Every US MD and DO with an active NPI has a profile here.

Why The Doctor Directory Uses the NPI Registry as Source of Truth

Three reasons:

  1. Coverage. Every US healthcare provider has an NPI. There is no US MD or DO practicing without one. Using NPI as source means we cover the entire population.
  2. Verifiability. Anyone can independently verify a profile by searching the NPI Registry directly. If our name, specialty, and address match the federal record, the identity is confirmed.
  3. Federal maintenance. CMS updates the NPI Registry continuously as providers add locations, change specialties, or deactivate. We refresh our source data on a rolling basis to stay current.

NPI vs State Medical License vs Board Certification

 What it confirmsWho issues itPublic?
NPI numberReal, credentialed provider identityCMS (federal)Yes
State medical licenseCurrent authority to practice medicine in a stateState medical boardOften yes, varies by state
ABMS board certificationAdvanced specialty training and examinationMember boards of ABMSYes, via certificationmatters.org

Frequently Asked Questions

What is the NPI Registry?

The National Provider Identifier (NPI) Registry is a public database maintained by the Centers for Medicare and Medicaid Services (CMS). It contains a unique 10-digit identifier for every US healthcare provider, along with name, primary practice address, specialty taxonomy code, and enrollment status. The registry is federally mandated under HIPAA and is the authoritative source of US provider identity.

How do I look up a doctor's NPI number?

Search by name at the official NPI Registry at npiregistry.cms.hhs.gov. The Doctor Directory also displays the NPI-derived specialty and primary practice location on every doctor profile page. Every US MD and DO has an NPI number; the number is public information.

Does the NPI Registry include patient reviews?

No. The NPI Registry is an identity database, not a review platform. It contains no reviews, ratings, quality scores, or patient feedback. Directories like The Doctor Directory layer patient reviews and other supplementary data on top of NPI-sourced profiles.

Can I trust that a doctor with an NPI is real?

Yes. Every NPI number is issued to a specific, credentialed healthcare provider. The registry does not confirm current state license status, malpractice history, or board certification, but the NPI itself is a strong identity signal maintained by a federal agency.

Reviewed by The Doctor Directory Editorial Team · NPI Registry facts verified against CMS documentation.
Last verified: 2026-07-28