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DR. GREGORY LEROY WALKER MD
NPI 1366508301
Internal Medicine in Baltimore, MD

Active since December 27, 2006PECOS Enrolled
3333 N CALVERT ST STE 585, BALTIMORE, MD 21218(410) 235-8858(410) 235-8904 Get Directions Write a Review

NPPES record last updated: November 19, 2021. Verified against the NPPES registry weekly; last sync: August 02, 2026.

About Dr. Gregory Leroy Walker Md NPPES

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

DR. GREGORY LEROY WALKER MD (NPI 1366508301) is an individual internal medicine provider in Baltimore, Maryland, licensed in Maryland (D0025662) and active in the NPI registry since December 2006. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1366508301
Entity TypeIndividualMale
Primary Taxonomy207R00000X
Provider Legal NameDR. GREGORY LEROY WALKERCredential: MD
Location Address3333 N CALVERT ST STE 585Baltimore, MD 21218-6514
Mailing Address3333 N Calvert St Ste 585Baltimore, MD 21218-6514 · (410) 235-8858 · Fax (410) 235-8904
Phone(410) 235-8858
Fax(410) 235-8904
Sole ProprietorYes
Enumeration DateDecember 27, 2006
Last NPPES UpdateNovember 19, 2021
NPPES CertifiedNovember 19, 2021
✔ NPI 1366508301 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in MD · D0025662
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
3333 N CALVERT ST STE 585, Baltimore, MD 21218
Open in Google Maps ↗

Other Identifiers 4

OtherW322Blue Cross & Blue Choice
Medicaid771001100MD
OtherOW45Blue Cross
Other110072704Railroad Medicare

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. Gregory Leroy Walker Md 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.

Areas of Expertise CMS Part B claims 8

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214
This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.
230 services58 patients
Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report 93000
An electrocardiogram (ECG) is a non-invasive test that records your heart's electrical activity. Using 12 leads attached to your body, it captures data to help identify heart conditions. A doctor interprets the results and provides a report.
49 services38 patients
Ultrasound study of arm and leg arteries 93922
An ultrasound study of arm and leg arteries is a non-invasive procedure that uses sound waves to create images of your arteries. It helps in checking blood flow, identifying blockages, or detecting other abnormalities in your arteries.
36 services33 patients
Test to measure expiratory airflow and volume 94010
This test, known as spirometry, assesses how well your lungs work. It measures how much air you can inhale, how much you can exhale and how quickly you can exhale. It's non-invasive and helps diagnose conditions like asthma or COPD.
36 services27 patients
Advance care planning, first 30 minutes 99497
Advance care planning is a process where you discuss your healthcare preferences with your doctor. This conversation, lasting up to 30 minutes, helps ensure your wishes are respected if you're unable to communicate them in the future. It's about your care, your way.
31 services30 patients
Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit G0439
An annual wellness visit is a yearly appointment with your primary care provider to create or update a personalized prevention plan. This plan helps prevent illness based on your current health and risk factors. It's a subsequent visit, meaning it follows an initial assessment.
18 services18 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 21218 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
$106.59 typical visit price
range $19.60 – $149.17
Typical copayment $26.64 (range $4.90 – $37.29)
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.

Referred Medical Equipment & Supplies CMS DME claims 4

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Blood glucose test or reagent strips for home blood glucose monitor, per 50 strips A4253
DME-Other DME · category DE017N
13 suppliers34 claims94 services$4.98 avg. paid by Medicare
Oxygen concentrator, single delivery port, capable of delivering 85 percent or greater oxygen concentration at the prescribed flow rate E1390
DME-Oxygen and Supplies · category DC002N
1 supplier12 claims12 services$71.82 avg. paid by Medicare
Portable oxygen concentrator, rental E1392
DME-Oxygen and Supplies · category DC002N
1 supplier12 claims12 services$36.44 avg. paid by Medicare
Supply allowance for therapeutic continuous glucose monitor (cgm), includes all supplies and accessories, 1 month supply = 1 unit of service K0553
DME-Other DME · category DE017N
4 suppliers20 claims20 services$174.79 avg. paid by Medicare
Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES 4

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

OCCUPATIONAL AND BEHAVIORAL THERAPIES
Prosthetic/Orthotic Supplier
3333 N CALVERT ST STE 585
BALTIMORE, MD 21218
Baltimore City (716) 725-1805
REHABILITATION AND WELLNESS CONSULTING, LLC
Prosthetic/Orthotic Supplier
3333 N CALVERT ST STE 585
BALTIMORE, MD 21218
Baltimore City (866) 667-2460
REHABILITATION AND WELLNESS CONSULTING, LLC
Clinic/Center (Infusion Therapy)
3333 N CALVERT ST STE 585
BALTIMORE, MD 21218
Baltimore City (866) 667-2460
SHAWN DHILLON, M.D., P.C.
Chiropractor
3333 N CALVERT ST STE 585
BALTIMORE, MD 21218
Baltimore City (410) 670-5500

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 Gregory Walker's NPI number?

The NPI number for Gregory Walker is 1366508301. It was assigned to this individual provider in the NPPES registry on December 27, 2006.

Where is Gregory Walker located?

Gregory Walker practices at 3333 N Calvert St Ste 585, Baltimore, MD 21218. The listed phone number is (410) 235-8858.

What is Gregory Walker's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Gregory Walker enrolled in Medicare?

Yes. Gregory Walker is registered in the Medicare PECOS enrollment system.

When was this NPI record last updated?

The NPPES record for Gregory Walker was last updated on November 19, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.