Healthcare Provider Taxonomy Codes Explained
When a provider registers an NPI, they choose one or more taxonomy codes that describe their specialty. These codes come from the National Uniform Claim Committee (NUCC) Health Care Provider Taxonomy and are how this site translates a cryptic NPPES record into a readable specialty.
Last updated June 10, 2026
What a taxonomy code is
A taxonomy code is a 10-character alphanumeric code that classifies a provider by type, classification, and area of specialization. For example, a code maps to *Allopathic & Osteopathic Physicians → Family Medicine*. The NUCC publishes and maintains the code set, updating it twice a year.
How the hierarchy works
- Grouping — the broadest bucket (e.g. *Allopathic & Osteopathic Physicians*).
- Classification — the specialty within that grouping (e.g. *Family Medicine*).
- Specialization — an optional sub-specialty (e.g. *Sports Medicine*).
Primary vs secondary taxonomy
A provider can list several taxonomy codes but designates one as primary. The primary taxonomy is what most directories — including this one — use as the provider's headline specialty. Secondary codes capture additional areas of practice.
Every taxonomy that appears in the registry has its own directory page with state-level breakdowns.
Browse specialtiesFrequently asked questions
Effectively yes for everyday purposes — the taxonomy code is the machine-readable form of the provider's specialty. This site maps each code to its NUCC display name.
Yes. Providers may list multiple taxonomy codes but must designate one as primary. The primary code is the one shown as the headline specialty.