What Are Healthcare Provider Taxonomy Codes?

How the NUCC taxonomy code set describes a provider's specialty, how the ten-character code is structured, and why a taxonomy code is self-reported rather than verified.

Reviewed August 20, 2026

A taxonomy code is a 10-character code that describes a health care provider's type of practice or area of specialization. It is reported on the NPI application and stored alongside the NPI in NPPES, which is why an NPI lookup can tell you not just who a provider is, but broadly what kind of care they provide.

Who maintains the code set

The Health Care Provider Taxonomy is maintained by the National Uniform Claim Committee (NUCC), an industry body that has run the code set's request and maintenance process through its Code Subcommittee since 2001. It is an external, non-medical administrative code set — it exists for electronic transactions, not for clinical purposes — and its current release, version 26.1, contains 883 codes.

NUCC publishes updates twice a year: a release in January, effective April 1, and a release in July, effective October 1. Codes are occasionally retired (deactivated for new use) rather than deleted, so a code already on a provider's record does not disappear from the reference set when it is no longer offered to new applicants.

How a code is structured

Each code carries a three-level hierarchy, from broadest to most specific:

Level	What it captures	Example
Grouping	The broad provider category	Allopathic & Osteopathic Physicians
Classification	The general type or specialty within that grouping	Internal Medicine
Specialization	A narrower area of specialization within the classification, when one applies	Cardiovascular Disease

Not every code has a specialization — many stop at the classification level, which is itself a complete, usable code. Every code also carries a definition, a plain-language description of the scope of practice it represents, and a section tag of Individual or Non-Individual reflecting whether NUCC designed the code primarily for a person or an organization.

Real examples

Code	Grouping	Classification	Specialization	Display name
207Q00000X	Allopathic & Osteopathic Physicians	Family Medicine	—	Family Medicine Physician
207RC0000X	Allopathic & Osteopathic Physicians	Internal Medicine	Cardiovascular Disease	Cardiovascular Disease Physician
163W00000X	Nursing Service Providers	Registered Nurse	—	Registered Nurse
367500000X	Physician Assistants & Advanced Practice Nursing Providers	Nurse Anesthetist, Certified Registered	—	Certified Registered Nurse Anesthetist
122300000X	Dental Providers	Dentist	—	Dentist
282N00000X	Hospitals	General Acute Care Hospital	—	General Acute Care Hospital

A provider can report up to 15 codes

An NPI record can carry up to 15 taxonomy codes, letting a provider who practices across more than one specialty represent all of them. Exactly one is marked the primary taxonomy — the one that best represents the provider's principal type of practice — and that primary code is what a directory typically uses to categorize the provider or organization for browsing and search.

Taxonomy codes are self-selected, not verified

Self-reported, not certified

A provider selects their own taxonomy code(s) based on their education, training, and licensure — NUCC's own guidance describes the code set as allowing providers to self-select the code that best represents their type of practice. CMS does not independently confirm that a provider's board certification or specialty training matches the code they chose, and NPPES does not cross-check a taxonomy code against a state license record.

In practice this means a taxonomy code is a strong, structured signal of what a provider says they do — reported in a standardized, auditable format rather than free text — but it is not independent confirmation of specialty credentials, in the same way an NPI is not confirmation of licensure.

See Does an NPI Mean a Provider Is Licensed? for the closely related point about the NPI itself.

Where to look one up

NPISignal's taxonomy directory lists every active code with the providers enumerated under it.
NUCC publishes the authoritative code set and search tool directly.

NUCC Health Care Provider Taxonomy — official code set and search — National Uniform Claim Committee

Sources

NUCC Health Care Provider Taxonomy — code set overview, structure, and maintenance — National Uniform Claim Committee. Accessed August 20, 2026.
NUCC Taxonomy Code Set Update Announcements (semiannual January/July release cadence) — National Uniform Claim Committee. Accessed August 20, 2026.
nucc_taxonomy_261.csv — version 26.1 code set (883 codes, verified row count) — National Uniform Claim Committee. Accessed August 20, 2026.