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Steward Medical Group, Inc

Internal Medicine Physician in Boston, MA · enumerated 2011 · authorized official Michael Callum, Ceo.

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

National Provider Identifier

1255600300

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Registry record

Entity type Organization (Type 2)
Legal business name Steward Medical Group, Inc
Other name <Unavail>
Parent organization Steward Healthcare System LLC
Practice address 500 Boylston St, Boston, MA, 02116
Phone (615) 467-4158
Fax (615) 467-1267
Enumeration date Dec 19, 2011
Last updated in NPPES Aug 13, 2020

Taxonomy & classification

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians Primary
207RC0000X Cardiovascular Disease Physician Allopathic & Osteopathic Physicians Secondary

Authorized official

Name Michael Callum
Title Ceo
Phone (617) 419-4702

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 is the NPI number for Steward Medical Group, Inc?
The NPI for Steward Medical Group, Inc is 1255600300, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for Steward Medical Group, Inc?
NPPES lists Michael Callum (Ceo) as the authorized official for this organization.

Providers at this address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2020-08-13.