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Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

DR. MARGARET CALLOWAY M.D.
NPI 1881677888
Internal Medicine - Infectious Disease in Bethesda, MD

Active since November 22, 2005PECOS Enrolled
4301 JONES BRIDGE RD, OFFICE OF THE DEAN, BETHESDA, MD 20814(301) 295-1602 Get Directions Write a Review

NPPES record last updated: July 13, 2026. Verified against the NPPES registry weekly; last sync: August 02, 2026.

About Dr. Margaret Calloway M.d. NPPES

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

DR. MARGARET CALLOWAY M.D. (NPI 1881677888) is an individual infectious disease provider in Bethesda, Maryland, licensed in California (G79915) and active in the NPI registry since November 2005. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1881677888
Entity TypeIndividualFemale
Primary Taxonomy207RI0200X
Provider Legal NameDR. MARGARET CALLOWAYCredential: M.D.
Location Address4301 JONES BRIDGE RD, OFFICE OF THE DEANBethesda, MD 20814-4712
Mailing Address1745 Algonquin RdFrederick, MD 21701-9344 · (301) 663-5063
Phone(301) 295-1602
Sole ProprietorNo
Enumeration DateNovember 22, 2005
Last NPPES UpdateJuly 13, 2026
✔ NPI 1881677888 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Infectious DiseaseAllopathic & Osteopathic Physicians
Taxonomy Code207RI0200X
License✔ Licensed in CA · G79915
Definition
An internist who deals with infectious diseases of all types and in all organ systems. Conditions requiring selective use of antibiotics call for this special skill. This physician often diagnoses and treats AIDS patients and patients with fevers which have not been explained. Infectious disease specialists may also have expertise in preventive medicine and travel medicine.
4301 JONES BRIDGE RD, Bethesda, MD 20814
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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 Calloway 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 20814 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
$147.85 typical visit price
range $65.18 – $194.86
Typical copayment $36.96 (range $16.29 – $48.71)
Most-billed visit code 99204
Established Patient
$113.72 typical visit price
range $21.40 – $158.88
Typical copayment $28.43 (range $5.35 – $39.72)
Most-billed visit code 99214
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.

GAYLE DENISE HAISCHER-ROLLO MD
Pediatrics (Neonatal-Perinatal Medicine)
4301 JONES BRIDGE RD
BETHESDA, MD 20814
Montgomery County (817) 845-4191
LEYLAND SKYLER FURR
Student in an Organized Health Care Education/Training Program
4301 JONES BRIDGE RD
BETHESDA, MD 20814
Montgomery County (301) 295-9474
JI WON AHN
Student in an Organized Health Care Education/Training Program
4301 JONES BRIDGE RD
BETHESDA, MD 20814
Montgomery County (800) 515-5257
ELYSE FIORE PIERRE MD
Family Medicine
4301 JONES BRIDGE RD
BETHESDA, MD 20814
Montgomery County (301) 295-3630
NICHOLAS DIFAZIO BSN
Student in an Organized Health Care Education/Training Program
4301 JONES BRIDGE RD
BETHESDA, MD 20814
Montgomery County (301) 295-9004
PRISCILLA BELLETTINI
Student in an Organized Health Care Education/Training Program
4301 JONES BRIDGE RD
BETHESDA, MD 20814
Montgomery County (301) 295-9004
DEREK PARADIS
General Practice
4301 JONES BRIDGE RD
BETHESDA, MD 20814
Montgomery County (800) 515-5257
MARK WALTER GREGG RN
Student in an Organized Health Care Education/Training Program
4301 JONES BRIDGE RD
BETHESDA, MD 20814
Montgomery County (301) 295-9004

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 Calloway's NPI number?

The NPI number for Margaret Calloway is 1881677888. It was assigned to this individual provider in the NPPES registry on November 22, 2005.

Where is Margaret Calloway located?

Margaret Calloway practices at 4301 Jones Bridge Rd Office Of The Dean, Bethesda, MD 20814. The listed phone number is (301) 295-1602.

What is Margaret Calloway's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Infectious Disease, with taxonomy code 207RI0200X.

Is Margaret Calloway enrolled in Medicare?

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

When was this NPI record last updated?

The NPPES record for Margaret Calloway was last updated on July 13, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 24 days 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.