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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Marissa Lynn O'Neill, TLLP

Psychologist in Midland, MI · enumerated 2016 · practices at Behavioral Medicine Associates of Mid Michigan PC.

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

National Provider Identifier

1033569868

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Registry record

Entity type Individual (Type 1)
Name Marissa Lynn O'Neill
Credential TLLP
Sex Female
Practice address Midland, MI, 48642
Phone (989) 832-9161
Fax (989) 832-8813
Enumeration date Jun 13, 2016
Last updated in NPPES May 22, 2025

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

103T00000X Psychologist Behavioral Health & Social Service Providers · License 6361005251 (MI) Primary

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

How do I verify Marissa O'Neill's NPI record?
Cross-check NPI 1033569868 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1033569868 active?
Yes, as of the latest NPPES snapshot, NPI 1033569868 is active (record last updated 2025-05-22).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-05-22.