Medicare Specialty to NPPES Taxonomy Crosswalk
A Medicare specialty often accepts several taxonomy codes, and one taxonomy code can be valid for several specialties. That mismatch is a common reason an enrolment application is returned. Search a specialty or a taxonomy code and see every pairing CMS actually accepts.
- 562Accepted specialty and taxonomy pairings
- 84Taxonomy codes valid for more than one specialty
- 58Specialties that accept more than one taxonomy
- 8Specialties the most ambiguous taxonomy maps to
Why enrolment applications are returned
Your NPPES record carries a taxonomy code. Your Medicare enrolment carries a specialty. They are different classification systems maintained for different purposes, and CMS publishes the list of pairings it will accept between them. Put a taxonomy on an application that CMS does not pair with the specialty you asked for and the application comes back, often weeks later.
The relationship is not one to one in either direction, which is what makes it awkward. Fifty-eight Medicare specialties accept more than one taxonomy, so picking any single one is not obviously right or wrong. Eighty-four taxonomy codes are valid for more than one specialty, and one is accepted for eight different ones.
Check both directions
Searching by specialty shows every taxonomy CMS will accept for it, which is what you want when completing an application. Searching by taxonomy code shows every specialty that code is valid for, which is what you want when an NPPES record is already set and you are working out which specialties remain open.
The crosswalk changes
CMS reissues this file periodically and pairings are added and removed. The release is named with the results, so you can tell whether the list you are working from is the current one.
Sources and methodology
Source: the CMS Medicare Provider and Supplier Taxonomy Crosswalk, read from the CMS public data API, August 2026 release.
Specialty descriptions, Medicare specialty codes, taxonomy codes and taxonomy descriptions are reproduced exactly as published. The counts of how many taxonomies a specialty accepts, and how many specialties a taxonomy is valid for, are computed from the file itself rather than taken from any secondary source.
No provider is identified, scored or ranked here.