133V00000X Registered Dietitian

Definition

A Registered Dietitian (RD)/Registered Dietitian Nutritionist (RDN) is an individual uniquely trained in the science of nutrition and practice of dietetics to design and provide medical nutrition therapy (MNT) and other evidence-based applications of the Nutrition Care Process (NCP) that exemplify the profession's systematic approach to providing high quality nutrition care. Registered dietitians provide MNT for the purpose of disease prevention or management, or to treat or rehabilitate an illness, injury, or condition, with the use of specific, indicated physical and cognitive nutrition care services comprised of one or more of the following aspects of the NCP: nutrition assessment/reassessment, nutrition diagnosis, nutrition intervention (e.g., nutrition counseling, therapeutic diet ordering, and nutrition education) and nutrition monitoring and evaluation.

— NUCC Health Care Provider Taxonomy, version 26.1

Where 133V00000X sits

• Group: Dietary & Nutritional Service Providers — code 3 of 13 in the group
• Classification: Dietitian, Registered 133V00000X

This is the general code for Dietitian, Registered. 8 more specific codes sit beneath it; pick one of those when the provider's training or certification matches it, and this one otherwise. A provider may report more than one taxonomy code on an NPI but marks one as primary.

Medicare

CMS's taxonomy crosswalk links 133V00000X to Medicare specialty 71 (Registered Dietitian or Nutrition Professional). That specialty — not the taxonomy code itself — is what Medicare enrollment records and uses for payment. 11,323 practitioners are enrolled under it nationally, and 8 other taxonomy codes map to the same specialty.

Other codes under the same Medicare specialty: 133VN1004X Pediatric Nutrition Registered Dietitian; 133VN1005X Renal Nutrition Registered Dietitian; 133VN1006X Metabolic Nutrition Registered Dietitian; 133VN1101X Gerontological Nutrition Registered Dietitian; 133VN1201X Obesity and Weight Management Nutrition Registered Dietitian; 133VN1301X Oncology Nutrition Registered Dietitian; 133VN1401X Pediatric Critical Care Nutrition Registered Dietitian; 133VN1501X Sports Dietetics Nutrition Registered Dietitian.

Related codes

History of 133V00000X

NUCC's earliest recorded change to 133V00000X is from 2019 (modified definition).

• 2019-07-01 — modified definition

Similar codes in other groups

If 133V00000X is not quite right, these codes in other groups share a word with it — often the same field practised by a different kind of provider:

• 163W00000X Registered Nurse (Nursing Service Providers)
• 163WR0006X Registered Nurse First Assistant (Nursing Service Providers)
• 367500000X Certified Registered Nurse Anesthetist (Physician Assistants & Advanced Practice Nursing Providers)
• 227900000X Registered Respiratory Therapist (Respiratory, Developmental, Rehabilitative and Restorative Service Providers)
• 246YR1600X Registered Record Administrator (Technologists, Technicians & Other Technical Service Providers)

Using 133V00000X

The code goes in the taxonomy field of the NPI application in NPPES, and on claims where a payer asks for it — box 24J (shaded) or 33b on the CMS-1500 with the ZZ qualifier, or the PRV segment of an 837 electronic claim. Payers match it against the taxonomy on the NPI record and, for Medicare, against the specialty on the enrollment, so all three should agree. To see which code a provider uses, search their NPI in the lookup.

Sources: NUCC Health Care Provider Taxonomy code set, version 26.1 (CSV); CMS Medicare Provider and Supplier Taxonomy Crosswalk, August 2026; CMS Medicare Fee-For-Service Public Provider Enrollment, extract of 2026-09-29. Checked 2026-10-24. Methodology.