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Deborah Ann Posthumus, P.A.

Physician Assistant in Muskegon, MI · enumerated 2005 · practices at Hpcn.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1255339479

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Registry record

Entity type Individual (Type 1)
Name Deborah Ann Posthumus
Credential P.A.
Sex Female
Practice address 6207 Harvey St, Ste A, Muskegon, MI, 49444
Phone (231) 799-2515
Fax (231) 799-2618
Enumeration date Jul 12, 2005
Last updated in NPPES Feb 13, 2012

Taxonomy & licenses

363A00000X Physician Assistant Physician Assistants & Advanced Practice Nursing Providers · License 5601002123 (MI) Primary
PA · Physician Assistant: A licensed clinician who practices medicine in collaboration with physicians, trained in a graduate PA program. About the PA 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.

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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 Deborah Posthumus?
Deborah Posthumus is registered in NPPES with the primary taxonomy of Physician Assistant. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2012-02-13.