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DR. MARGARET MARY BRENNAN M.D.
NPI 1851489207
Internal Medicine - Cardiovascular Disease in Baltimore, MD

Active since October 11, 2006PECOS Enrolled
6569 N CHARLES ST, SUITE 600, BALTIMORE, MD 21204(443) 849-8989 Get Directions Write a Review

NPPES record last updated: September 14, 2022. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Sep 14, 2022, Feb 8, 2017 (2 updates tracked since 2017).

About Dr. Margaret Mary Brennan M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. MARGARET MARY BRENNAN M.D. (NPI 1851489207) is an individual cardiovascular disease provider in Baltimore, Maryland, licensed in Maryland (D35595) and active in the NPI registry since October 2006. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1851489207
Entity TypeIndividualFemale
Primary Taxonomy207RC0000X
Provider Legal NameDR. MARGARET MARY BRENNANCredential: M.D.
Location Address6569 N CHARLES ST, SUITE 600Baltimore, MD 21204-6831
Mailing Address6201 Greenleigh AveMiddle River, MD 21220-2004
Phone(443) 849-8989
Sole ProprietorNo
Enumeration DateOctober 11, 2006
Last NPPES UpdateSeptember 14, 20222 updates tracked since enumeration
NPPES CertifiedSeptember 14, 2022
✔ NPI 1851489207 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Cardiovascular DiseaseAllopathic & Osteopathic Physicians
Taxonomy Code207RC0000X
Licenses✔ Licensed in MD · D35595✔ Licensed in TN · 15409
Definition
An internist who specializes in diseases of the heart and blood vessels and manages complex cardiac conditions such as heart attacks and life-threatening, abnormal heartbeat rhythms.
6569 N CHARLES ST, Baltimore, MD 21204
Open in Google Maps ↗

Other Identifiers 1

Medicaid533771200MD

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Margaret Mary Brennan M.d. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 21204 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$139.05 typical visit price
range $60.73 – $183.44
Typical copayment $34.76 (range $15.18 – $45.86)
Most-billed visit code 99204
Established Patient
$75.47 typical visit price
range $19.60 – $149.17
Typical copayment $18.86 (range $4.90 – $37.29)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

DR. JOHN R SAUNDERS JR. M.D.
Surgery (Surgical Oncology)
6569 N CHARLES ST, SUITE 401
BALTIMORE, MD 21204
Baltimore County (443) 849-8940
DR. GINNY M MERRYMAN M.D.
Obstetrics & Gynecology
6569 N CHARLES ST, SUITE 501
BALTIMORE, MD 21204
Baltimore County (410) 938-8960
GHASSAN G SINADA D.D.S.
Dentist (Oral and Maxillofacial Surgery)
6569 N CHARLES ST, PPW SUITE 601
BALTIMORE, MD 21204
Baltimore County (443) 519-5293
DANIEL A SHERWOOD SLP
Speech-Language Pathologist
6569 N CHARLES ST, PHYSICIANS PAVILION WEST, SUITE 401
BALTIMORE, MD 21204
Baltimore County (443) 849-2087
GREATER BALTIMORE MEDICAL CENTER, INC.
Ophthalmology
6569 N CHARLES ST, SUITE 305
BALTIMORE, MD 21204
Baltimore County (443) 849-2658
DR. MARY LOUISE COLLINS M.D.
Ophthalmology
6569 N CHARLES ST, SUITE 505
BALTIMORE, MD 21204
Baltimore County (443) 849-2196
DR. TANVI M. SHAH M.D.
Ophthalmology
6569 N CHARLES ST, PPW SUITE 505
BALTIMORE, MD 21204
Baltimore County (443) 849-2106
DR. DAVID PATRICK COLL M.D.
Surgery (Vascular Surgery)
6569 N CHARLES ST, STE 701
BALTIMORE, MD 21204
Baltimore County (443) 849-3431

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Margaret Brennan's NPI number?

The NPI number for Margaret Brennan is 1851489207. It was assigned to this individual provider in the NPPES registry on October 11, 2006.

Where is Margaret Brennan located?

Margaret Brennan practices at 6569 N Charles St Suite 600, Baltimore, MD 21204. The listed phone number is (443) 849-8989.

What is Margaret Brennan's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Cardiovascular Disease, with taxonomy code 207RC0000X.

Is Margaret Brennan enrolled in Medicare?

Yes. Margaret Brennan is registered in the Medicare PECOS enrollment system.

When was this NPI record last updated?

The NPPES record for Margaret Brennan was last updated on September 14, 2022. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.