Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Dr. Mark Daniel Holsey, D.O.
Psychiatry Physician in Norman, OK · enumerated 2015.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1992184485
See something wrong? Report a correction
Registry record
Entity type Individual (Type 1)
Name Dr. Mark Daniel Holsey
Credential D.O.
Sex Male
Practice address 2268 36th Ave Nw Ste 120, Norman, OK, 73072
Phone (405) 876-8118
Fax (936) 244-4621
Enumeration date May 29, 2015
Last updated in NPPES Jul 25, 2026
Taxonomy & licenses
DO · Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD.
About the DO credential
What is an NPI number?
A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.
Frequently asked questions
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Mark Holsey?
Mark Holsey is registered in NPPES with the primary taxonomy of Psychiatry Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Other providers at this practice address
Browse all →Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2026-07-25.