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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Claire Johnson, L.C.S.W.

Case Manager/Care Coordinator in Charlestown, MA · enumerated 2016.

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

National Provider Identifier

1891142550

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Registry record

Entity type Individual (Type 1)
Name Claire Johnson
Credential L.C.S.W.
Sex Female
Practice address 529 Main St, Suite 100, Charlestown, MA, 02129
Phone (617) 864-8140
Fax (617) 864-2541
Enumeration date May 23, 2016
Last updated in NPPES May 23, 2016

Taxonomy & licenses

171M00000X Case Manager/Care Coordinator Other Service Providers Primary
LCSW · Licensed Clinical Social Worker: A social worker licensed for clinical practice including mental-health therapy. About the LCSW 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

How do I verify Claire Johnson's NPI record?
Cross-check NPI 1891142550 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1891142550 active?
Yes, as of the latest NPPES snapshot, NPI 1891142550 is active (record last updated 2016-05-23).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2016-05-23.