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Greenfield Ob-Gyn Associates, PC

Gynecology Physician in Greenfield, MA · enumerated 2006 · authorized official William Callahan, Owner.

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

National Provider Identifier

1306915285

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Registry record

Entity type Organization (Type 2)
Legal business name Greenfield Ob-Gyn Associates, PC
Practice address 5 Park St, Greenfield, MA, 01301
Phone (413) 773-5481
Fax (413) 774-3244
Enumeration date Nov 7, 2006
Last updated in NPPES Oct 21, 2008

Taxonomy & classification

207VG0400X Gynecology Physician Allopathic & Osteopathic Physicians · License 28664 (MA) Primary

Authorized official

Name William Callahan
Title Owner
Phone (413) 773-5481

Other identifiers

Identifier Type State Issuer
9734686 Medicaid MA -
M13127 Other MA BCMA GROUP

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

Who is the authorized official for Greenfield Ob-Gyn Associates, PC?
NPPES lists William Callahan (Owner) as the authorized official for this organization.
What is the NPI number for Greenfield Ob-Gyn Associates, PC?
The NPI for Greenfield Ob-Gyn Associates, PC is 1306915285, a Type 2 (organization) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-10-21.