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Mrs. Mary B O'Brien, RN-C, FNP, MS

Family Nurse Practitioner in Allendale, MI · enumerated 2007.

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

National Provider Identifier

1336276864

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Registry record

Entity type Individual (Type 1)
Name Mrs. Mary B O'Brien
Credential RN-C, FNP, MS
Sex Female
Practice address 10383 42nd Ave, Allendale, MI, 49401
Phone (616) 252-6030
Fax (616) 252-6035
Enumeration date Feb 28, 2007
Last updated in NPPES Feb 21, 2012

Taxonomy & licenses

363LF0000X Family Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 4704107338 (MI) Primary
FNP · Family Nurse Practitioner: A nurse practitioner certified in family practice across the lifespan. About the FNP 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

What is the NPI number for Mary O'Brien?
The National Provider Identifier (NPI) for Mary O'Brien is 1336276864, a Type 1 (individual) record in the CMS NPPES registry.
Where does Mary O'Brien practice?
The practice location on file with NPPES is in Allendale, MI. Providers can have multiple locations; NPPES lists the primary practice address.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2012-02-21.