224Z00000X Occupational Therapy Assistant

Definition

An occupational therapy assistant is a person who has graduated from an occupational therapy assistant program accredited by the Accreditation Council for Occupational Therapy Education (ACOTE) or predecessor organizations, has successfully completed a period of supervised fieldwork experience required by the accredited occupational therapy assistant program, has passed a nationally recognized entry-level examination for occupational therapy assistants, and fulfills state requirements for licensure, certification, or registration. An occupational therapy assistant provides interventions under the supervision of an occupational therapist which emphasize the therapeutic use of everyday life activities (i.e., occupations) with individuals or groups for the purpose of facilitating participation in roles and situations and in home, school, workplace, community and other settings. Occupational therapy services are provided for the purpose of promoting health and wellness and are provided to those who have or are at risk for developing an illness, injury, disease, disorder, condition, impairment, disability, activity limitation, or participation restriction. Occupational therapy assistants address the physical, cognitive, psychosocial, sensory, and other aspects of occupational performance in a variety of contexts to support engagement in everyday life activities that affect health, well-being, and quality of life.

— NUCC Health Care Provider Taxonomy, version 26.1

Where 224Z00000X sits

• Group: Respiratory, Developmental, Rehabilitative and Restorative Service Providers — code 23 of 82 in the group
• Classification: Occupational Therapy Assistant 224Z00000X

This is the general code for Occupational Therapy Assistant. 4 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

224Z00000X has no entry in the CMS Medicare Provider and Supplier Taxonomy Crosswalk. That usually means Medicare does not enroll this kind of provider under its own specialty — the provider can still hold an NPI and use this code on claims to other payers.

Related codes

History of 224Z00000X

NUCC's earliest recorded change to 224Z00000X is from 2008 (definition changed, source changed).

• 2008-07-01 — definition changed, source changed

Similar codes in other groups

If 224Z00000X 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:

• 207UN0902X Nuclear Imaging & Therapy Physician (Allopathic & Osteopathic Physicians)
• 2083X0100X Occupational Medicine Physician (Allopathic & Osteopathic Physicians)
• 2083P0500X Preventive Medicine/Occupational Environmental Medicine Physician (Allopathic & Osteopathic Physicians)
• 106E00000X Assistant Behavior Analyst (Behavioral Health & Social Service Providers)
• 111NX0100X Occupational Health Chiropractor (Chiropractic Providers)
• 126800000X Dental Assistant (Dental Providers)

Using 224Z00000X

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). Checked 2026-10-24. Methodology.