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GREGORY DAVIS MACKAY M.D.
NPI 1346277613
Internal Medicine - Gastroenterology in Vero Beach, FL

Active since June 26, 2006PECOS Enrolled
89.89/100
CMS Quality Rating
3745 11TH CIR, SUITE 101, VERO BEACH, FL 32960(772) 299-3211(772) 299-3517 Get Directions Write a Review

NPPES record last updated: January 22, 2018. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Gregory Davis Mackay M.d. NPPES

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

GREGORY DAVIS MACKAY M.D. (NPI 1346277613) is an individual gastroenterology provider in Vero Beach, Florida, licensed in Florida (ME 60347) and active in the NPI registry since June 2006. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1346277613
Entity TypeIndividualMale
Primary Taxonomy207RG0100X
Provider Legal NameGREGORY DAVIS MACKAYCredential: M.D.
Location Address3745 11TH CIR, SUITE 101Vero Beach, FL 32960-4837
Mailing Address3450 11th Ct Ste 206Vero Beach, FL 32960-5012 · (772) 299-3511 · Fax (772) 299-3517
Phone(772) 299-3211
Fax(772) 299-3517
Sole ProprietorNo
Enumeration DateJune 26, 2006
Last NPPES UpdateJanuary 22, 2018
✔ NPI 1346277613 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians
Taxonomy Code207RG0100X
License✔ Licensed in FL · ME 60347
Definition
An internist who specializes in diagnosis and treatment of diseases of the digestive organs including the stomach, bowels, liver and gallbladder. This specialist treats conditions such as abdominal pain, ulcers, diarrhea, cancer and jaundice and performs complex diagnostic and therapeutic procedures using endoscopes to visualize internal organs.
3745 11TH CIR, Vero Beach, FL 32960
Open in Google Maps ↗

Other Identifiers 3

Other100015007FL · Rr Medicare
Other12603FL · Blue Cross
MedicaidO55359000FL

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter from Superior HealthPlan, Ambetter Health, Ambetter of Alabama and more.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Gregory Davis Mackay 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.

Medicare Billing Reassignment

Medicare enrollment records show Gregory Mackay reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Indian River Health Services Inc
Same address
Urology
3745 11TH CIRCLE, SUITE 103
Vero Beach, FL 32960
  • Reassigned Medicare billing, Florida enrollment
  • 505 clinicians in this Medicare group
NPI 1376864108 (772) 794-9771

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

Areas of Expertise CMS Part B claims

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.

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232
Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.
22 services16 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 32960 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
$135.56 typical visit price
range $58.56 – $179.05
Typical copayment $33.89 (range $14.64 – $44.76)
Most-billed visit code 99204
Established Patient
$103.21 typical visit price
range $18.44 – $144.68
Typical copayment $25.80 (range $4.61 – $36.17)
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.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

89.89/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored through an Alternative Payment Model
Quality75.75
Promoting Interoperability100
Improvement Activities40

Other Providers at the Same Location NPPES 10

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

JOSEPH JOHN ZEREGA M.D.
Internal Medicine (Gastroenterology)
3745 11TH CIR, SUITE 101
VERO BEACH, FL 32960
Indian River County (772) 299-3511
CHARLES EUGENE EBERHART M.D.
Internal Medicine (Gastroenterology)
3745 11TH CIR, SUITE 101
VERO BEACH, FL 32960
Indian River County (772) 299-3511
DAVID ROBERT BIEZUNSKI M.D.
Internal Medicine (Endocrinology, Diabetes & Metabolism)
3745 11TH CIR
VERO BEACH, FL 32960
Indian River County (772) 589-0580
NEAL LAMAR SHAPPIE APRN, FNP-C
Nurse Practitioner (Adult Health)
3745 11TH CIR
VERO BEACH, FL 32960
Indian River County (772) 589-0580
CHRISTOPHER P TARDIF MD
Urology
3745 11TH CIR, SUITE 103
VERO BEACH, FL 32960
Indian River County (772) 794-9771
INDIAN RIVER HEALTH SERVICES INC
Internal Medicine (Gastroenterology)
3745 11TH CIR, SUITE 101
VERO BEACH, FL 32960
Indian River County (772) 299-3511
UROLOGY ASSOCIATES OF VERO BEACH LLC
Urology
3745 11TH CIR, SUITE 103
VERO BEACH, FL 32960
Indian River County (772) 794-9771
HEIDI SUE EMPEY ARNP
Nurse Practitioner
3745 11TH CIR, SUITE 101
VERO BEACH, FL 32960
Indian River County (772) 299-3511

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 Mackay's NPI number?

The NPI number for Gregory Mackay is 1346277613. It was assigned to this individual provider in the NPPES registry on June 26, 2006.

Where is Gregory Mackay located?

Gregory Mackay practices at 3745 11th Cir Suite 101, Vero Beach, FL 32960. The listed phone number is (772) 299-3211.

What is Gregory Mackay's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Is Gregory Mackay enrolled in Medicare?

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

Which organization bills Medicare for Gregory Mackay's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Gregory Mackay reassigns Medicare benefits to Indian River Health Services Inc (Vero Beach, FL). The 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 Gregory Mackay's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Gregory Mackay accept?

Health plans from Ambetter Health, Ambetter from Superior HealthPlan, Ambetter of Alabama, Cigna HealthCare of Florida, Inc. and Cigna Healthcare and 2 other insurers list Gregory Mackay 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 Gregory Mackay was last updated on January 22, 2018. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 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.