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Dr. Benjamin Louis Mazer, M.D.

Dr. Benjamin Louis Mazer is a Anatomic Pathology & Clinical Pathology Physician provider (Pathology) practicing in Baltimore, MD, registered in the NPPES registry with NPI 1689022352 since 2016. The credential MD stands for Doctor of Medicine.

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NPI 1689022352
Entity type Individual (Type 1)
Name Dr. Benjamin Louis Mazer
Credential M.D.
Sex Male
Practice address 600 N WOLFE ST, Baltimore, MD, 21287
Phone 4109553580
Fax 4105500075
Enumeration date 2016-06-02
Last updated in NPPES 2021-04-14

Taxonomy & licenses

Taxonomy code Specialty Primary License State
207ZP0102X Anatomic Pathology & Clinical Pathology Physician Primary D88601 MD

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

Copy-ready billing details
Provider: Benjamin Mazer, M.D.
NPI: 1689022352
Taxonomy: 207ZP0102X (Anatomic Pathology & Clinical Pathology Physician)
Address: 600 N WOLFE ST, Baltimore, MD, 21287

Other providers at this practice address

NPI Name Type Specialty Location
1457354821 Earl Craven Individual Ophthalmology Physician Baltimore, MD
1588667943 Laura Hostovich Individual Nurse Practitioner Baltimore, MD
1801891080 Johns Hopkins University Organization Cardiovascular Disease Physician Baltimore, MD
1356346100 Johns Hopkins University Organization Neurology Physician Baltimore, MD
1013913789 Johns Hopkins University Organization Orthopaedic Surgery Physician Baltimore, MD
1922004696 Johns Hopkins University Organization Otolaryngology Physician Baltimore, MD
1740286418 Johns Hopkins University Organization Anesthesiology Physician Baltimore, MD
1659377323 Johns Hopkins University Organization Dermatology Physician Baltimore, MD

Verify this record

Cross-check NPI 1689022352 against the authoritative CMS record: view Dr. Benjamin Louis Mazer on the official NPPES registry .

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 or validate an NPI number.

Frequently asked questions

How do I verify Benjamin Mazer's NPI record?
Cross-check NPI 1689022352 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1689022352 active?
Yes — as of the latest NPPES snapshot, NPI 1689022352 is active (record last updated 2021-04-14).

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2021-04-14.