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GREINER INTERNAL MEDICINE, P.C.
NPI 1831068501
Internal Medicine in Tulsa, OK

Active since November 01, 2025CLIA 37D2333367 · Waiver
4785 E 91ST ST STE 200, TULSA, OK 74137(918) 215-3557(833) 764-5184 Get Directions Write a Review

NPPES record last updated: August 10, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Greiner Internal Medicine, P.c. NPPES

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

GREINER INTERNAL MEDICINE, P.C. (NPI 1831068501) is a healthcare organization registered as an internal medicine in Tulsa, Oklahoma and active in the NPI registry since November 2025. The organization holds a CLIA Waiver certificate valid through November 3, 2027 and lists Benjamin Houston Greiner, Owner, as its authorized official.

NPPES Registry Identity

NPI1831068501
Entity TypeOrganization
Primary Taxonomy207R00000X
Legal Business NameGREINER INTERNAL MEDICINE, P.C.
Location Address4785 E 91ST ST STE 200Tulsa, OK 74137-2839
Mailing Address4785 E 91st St Ste 200Tulsa, OK 74137-2839 · (918) 215-3557 · Fax (833) 764-5184
Phone(918) 215-3557
Fax(833) 764-5184
Organization SubpartNo
Authorized OfficialBenjamin Houston GreinerOwner · (918) 215-3557
Enumeration DateNovember 1, 2025
Last NPPES UpdateAugust 10, 2026
NPPES CertifiedAugust 10, 2026
✔ NPI 1831068501 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
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.
4785 E 91ST ST STE 200, Tulsa, OK 74137
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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

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Blue Cross and Blue Shield of Oklahoma.Insurance ›

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Greiner Internal Medicine, P.c. 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 Greiner Internal Medicine, P.C., which bills Medicare for the services this clinician delivers.

Clinician (1)

Benjamin Greiner, DO, MPH
Internal Medicine
NPI 1902428212
6600 S YALE AVE STE 600
Tulsa, OK 74136
(918) 491-5990
✔ PECOS✔ Accepts Medicare2.4 mi

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

CLIA Laboratory Certificates CMS CLIA

Laboratory certificates issued under the Clinical Laboratory Improvement Amendments (CLIA) program, which sets federal quality standards for human laboratory testing in the United States. There is no official CMS crosswalk between CLIA and NPI numbers; these certificates are associated with this NPI by matching facility names, locations and phone numbers in the CMS CLIA registry.

Certificate of Waiver 37D2333367

Greiner Internal Medicine PC · Tulsa, OK
Active · expires Nov 3, 2027
CLIA Number37D2333367
Laboratory TypePhysician Office
Certificate Effective DateNovember 4, 2025
Certificate Expiration DateNovember 3, 2027
Laboratory DirectorBenjamin H. Greiner
Laboratory Phone(918) 615-4015
Laboratory LocationGreiner Internal Medicine PC4785 E 91st St, Ste 200, Tulsa, OK 74137
CLIA data matches this NPI record on: Address Name
This certificate is issued to a laboratory to perform only waived tests.

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 Greiner Internal Medicine, P.C.'s NPI number?

The NPI number for Greiner Internal Medicine, P.C. is 1831068501. It was assigned to this organization in the NPPES registry on November 1, 2025.

Where is Greiner Internal Medicine, P.C. located?

Greiner Internal Medicine, P.C. is located at 4785 E 91st St Ste 200, Tulsa, OK 74137. The listed phone number is (918) 215-3557.

What is Greiner Internal Medicine, P.C.'s specialty?

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

Is Greiner Internal Medicine, P.C. enrolled in Medicare?

Yes. Greiner Internal Medicine, P.C. is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Greiner Internal Medicine, P.C.?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Internal Medicine) reassigns their Medicare billing to Greiner Internal Medicine, P.C.. 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.

Does Greiner Internal Medicine, P.C. hold a CLIA laboratory certificate?

Yes. A Certificate of Waiver (number 37D2333367) is associated with this NPI, valid through November 3, 2027. CLIA certificates authorize laboratory testing under the federal Clinical Laboratory Improvement Amendments program.

What insurance does Greiner Internal Medicine, P.C. accept?

Health plans from Blue Cross and Blue Shield of Oklahoma list Greiner Internal Medicine, P.C. as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Greiner Internal Medicine, P.C. was last updated on August 10, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 months 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.