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MARK H GREGORY MD PC
NPI 1033588256
Internal Medicine in Saint Louis, MO

Active since September 17, 2015
555 N NEW BALLAS RD, SUITE 101, SAINT LOUIS, MO 63141(314) 872-8470(314) 872-8471 Get Directions Write a Review

NPPES record last updated: September 17, 2015. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Mark H Gregory Md Pc NPPES

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

MARK H GREGORY MD PC (NPI 1033588256) is a healthcare organization registered as an internal medicine in Saint Louis, Missouri and active in the NPI registry since September 2015. The organization lists Mark Gregory, Owner, as its authorized official.

NPPES Registry Identity

NPI1033588256
Entity TypeOrganization
Primary Taxonomy207R00000X
Legal Business NameMARK H GREGORY MD PC
Location Address555 N NEW BALLAS RD, SUITE 101Saint Louis, MO 63141-6825
Mailing AddressPo Box 445Sullivan, MO 63080-0445 · (573) 468-6501 · Fax (573) 468-6502
Phone(314) 872-8470
Fax(314) 872-8471
Organization SubpartNo
Authorized OfficialMark GregoryOwner · (314) 872-8470
Enumeration DateSeptember 17, 2015
✔ NPI 1033588256 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in MO · 100578
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.
555 N NEW BALLAS RD, Saint Louis, MO 63141
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Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Mark H Gregory Md Pc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 1 clinician reassigns Medicare billing to Mark H Gregory MD PC, which bills Medicare for the services this clinician delivers.

Clinician (1)

Mark Gregory, MD
Internal Medicine
NPI 1104843663
555 N NEW BALLAS RD SUITE 110
Saint Louis, MO 63141
(314) 872-8470
✔ PECOS✔ Accepts Medicare1.4 mi

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

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 Mark H Gregory MD PC's NPI number?

The NPI number for Mark H Gregory MD PC is 1033588256. It was assigned to this organization in the NPPES registry on September 17, 2015.

Where is Mark H Gregory MD PC located?

Mark H Gregory MD PC is located at 555 N New Ballas Rd Suite 101, Saint Louis, MO 63141. The listed phone number is (314) 872-8470.

What is Mark H Gregory MD PC's specialty?

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

Is Mark H Gregory MD PC enrolled in Medicare?

Yes. Mark H Gregory MD PC is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Mark H Gregory MD PC?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Internal Medicine) reassigns their Medicare billing to Mark H Gregory MD PC. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Mark H Gregory MD PC was last updated on September 17, 2015. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 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.