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MARCUS MAYUS MD INC
NPI 1780341743
Internal Medicine in Greenwich, CT

Active since November 24, 2021
81 HOLLY HILL LN FL 3, GREENWICH, CT 06830(203) 869-5515(203) 869-5765 Get Directions Write a Review

NPPES record last updated: November 24, 2021. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Marcus Mayus Md Inc NPPES

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

MARCUS MAYUS MD INC (NPI 1780341743) is a healthcare organization registered as an internal medicine in Greenwich, Connecticut and active in the NPI registry since November 2021. The organization lists Marcus Mayus, Physician/owner, as its authorized official.

NPPES Registry Identity

NPI1780341743
Entity TypeOrganization
Primary Taxonomy207R00000X
Legal Business NameMARCUS MAYUS MD INC
Location Address81 HOLLY HILL LN FL 3Greenwich, CT 06830-6071
Mailing Address81 Holly Hill Ln Fl 3Greenwich, CT 06830-6071 · (203) 869-5515 · Fax (203) 869-5765
Phone(203) 869-5515
Fax(203) 869-5765
Organization SubpartNo
Authorized OfficialMarcus MayusPhysician/owner · (203) 869-5515
Enumeration DateNovember 24, 2021
NPPES CertifiedNovember 24, 2021
✔ NPI 1780341743 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.
81 HOLLY HILL LN FL 3, Greenwich, CT 06830
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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 Anthem Blue Cross and Blue Shield.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)

Marcus Mayus Md Inc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

2

Medicare enrollment records show 2 clinicians reassign Medicare billing to Marcus Mayus MD Inc, which bills Medicare for the services they deliver. Of these, 1 practice at this address and 2 within 10 miles. They are listed nearest first.

Clinicians, nearest first (2)

Marcus Mayus, M.D.
Internal Medicine
NPI 1073734935
81 HOLLY HILL LN FL 3
Greenwich, CT 06830
(203) 869-5515
✔ PECOS✔ Accepts MedicareSame address
David Lo, M.D.
Internal Medicine
NPI 1841602273
51 SCHUYLER AVE
Stamford, CT 06902
(203) 327-1187
✔ PECOS✔ Accepts Medicare5.7 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 Marcus Mayus MD Inc's NPI number?

The NPI number for Marcus Mayus MD Inc is 1780341743. It was assigned to this organization in the NPPES registry on November 24, 2021.

Where is Marcus Mayus MD Inc located?

Marcus Mayus MD Inc is located at 81 Holly Hill Ln Fl 3, Greenwich, CT 06830. The listed phone number is (203) 869-5515.

What is Marcus Mayus MD Inc's specialty?

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

Is Marcus Mayus MD Inc enrolled in Medicare?

Yes. Marcus Mayus MD Inc is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Marcus Mayus MD Inc?

According to the CMS Revalidation Reassignment List (October 2026 release), 2 clinicians, all in Internal Medicine, reassign their Medicare billing to Marcus Mayus MD Inc. 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. Of these, 1 practice at this address and 2 within 10 miles. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

What insurance does Marcus Mayus MD Inc accept?

Health plans from Anthem Blue Cross and Blue Shield list Marcus Mayus MD Inc 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 Marcus Mayus MD Inc was last updated on November 24, 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.