Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. Brian Terence Callahan Jr., M.D.

Surgery Physician in Concord, MA · enumerated 2006.

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

National Provider Identifier

1174558217

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Registry record

Entity type Individual (Type 1)

Name Dr. Brian Terence Callahan Jr.

Credential M.D.

Sex Male

Practice address 131 Ornac, Concord, MA, 01742

Phone (978) 287-3547

Enumeration date Jul 11, 2006

Last updated in NPPES Feb 20, 2014

Taxonomy & licenses

208600000X Surgery Physician Allopathic & Osteopathic Physicians · License 60166 (MA) Primary

MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD 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.

Read the full guide → Validate an NPI →

Frequently asked questions

Is NPI 1174558217 active?

Yes, as of the latest NPPES snapshot, NPI 1174558217 is active (record last updated 2014-02-20).

How do I verify Brian Callahan's NPI record?

Cross-check NPI 1174558217 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2014-02-20.