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Cornerstone Montgomery, Inc.

Cornerstone Montgomery, Inc. is a healthcare organization registered as Case Management Agency in Leonardtown, MD, holding Type 2 (organization) NPI 1689376998 since 2023. The authorized official on file is Michael Ostrowski, Billing Manager.

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NPI 1689376998
Entity type Organization (Type 2)
Legal business name Cornerstone Montgomery, Inc.
Practice address 41900 FENWICK ST, Leonardtown, MD, 20650
Phone 3014759315
Fax 3014759317
Enumeration date 2023-03-20
Last updated in NPPES 2023-03-20

Authorized official

Name Michael Ostrowski
Title Billing Manager
Phone 3014934200

Taxonomy & classification

Taxonomy code Specialty Primary License State
251B00000X Case Management Agency Primary
Copy-ready billing details
Provider: Cornerstone Montgomery, Inc.
NPI: 1689376998
Taxonomy: 251B00000X (Case Management Agency)
Address: 41900 FENWICK ST, Leonardtown, MD, 20650

Providers at this address

NPI Name Type Specialty Location
1265487888 H Miller Individual Cognitive & Behavioral Psychologist Leonardtown, MD
1245346766 Melanie Ledig Individual Social Worker Leonardtown, MD
1215043666 Psychological Services Center, LLC Organization Counselor Leonardtown, MD
1619083110 Jennifer Willoughby Individual Psychologist Leonardtown, MD
1891801304 Paul Richard Individual Social Worker Leonardtown, MD
1871744946 Psychotherapeutic Services of Southern Maryland Organization Case Management Agency Leonardtown, MD
1497907067 Alissa S. Jones, Ph.D., P.A. Organization Psychologist Leonardtown, MD
1184958522 Jennifer Carroll Individual Clinical Social Worker Leonardtown, MD

Verify this record

Cross-check NPI 1689376998 against the authoritative CMS record: view Cornerstone Montgomery, Inc. on the official NPPES registry .

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. Read the full guide or validate an NPI number.

Frequently asked questions

Where is Cornerstone Montgomery, Inc. located?
The practice location on file with NPPES is in Leonardtown, MD.
How current is this record?
Data comes from the CMS NPPES public dissemination file; this record was last updated in NPPES on 2023-03-20. Verify at npiregistry.cms.hhs.gov.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2023-03-20.