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

Mrs. Mary Carolyn Treuer, SLP

Speech-Language Pathologist in Livingston, NJ · enumerated 2018.

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

National Provider Identifier

1639646615

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Registry record

Entity type Individual (Type 1)
Name Mrs. Mary Carolyn Treuer
Credential SLP
Sex Female
Practice address Livingston, NJ, 07039
Phone (973) 535-0543
Enumeration date Oct 29, 2018
Last updated in NPPES Oct 29, 2018

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

Taxonomy & licenses

235Z00000X Speech-Language Pathologist Speech, Language and Hearing Service Providers · License 41YS000903200 (NJ) Primary
SLP · Speech-Language Pathologist: A licensed clinician treating speech, language, and swallowing disorders. About the SLP 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

Where does Mary Treuer practice?
The practice location on file with NPPES is in Livingston, NJ. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Mary Treuer?
The National Provider Identifier (NPI) for Mary Treuer is 1639646615, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2018-10-29.