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Charles E. Streff

Clinical Psychologist in Acton, MA · enumerated 2007 · authorized official Charles Streff, Owner.

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

National Provider Identifier

1700921673

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Registry record

Entity type Organization (Type 2)
Legal business name Charles E. Streff
Other name <Unavail>
Practice address 532 Great Rd, Acton, MA, 01720
Phone (978) 263-0439
Fax (978) 486-3140
Enumeration date Feb 20, 2007
Last updated in NPPES Jul 20, 2007

Taxonomy & classification

103T00000X Psychologist Behavioral Health & Social Service Providers Secondary
103TC0700X Clinical Psychologist Behavioral Health & Social Service Providers Primary
163WP0808X Psychiatric/Mental Health Registered Nurse Nursing Service Providers Secondary

Authorized official

Name Charles Streff
Title Owner
Phone (978) 263-0439

Other identifiers

Identifier Type State Issuer
W10613 Other MA BLUE CROSS
612861 Other MA TUFTS

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 type of organization is Charles E. Streff?
Charles E. Streff is registered in NPPES as a Clinical Psychologist (its primary provider taxonomy).
What is a Type 2 NPI?
A Type 2 NPI identifies an organization (group practice, hospital, pharmacy, lab), while Type 1 NPIs identify individual providers. Organizations bill under their Type 2 NPI.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-20.