Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

GIANNA NICOLE NIEMEIER VERMEYS MD
NPI 1235926411
Internal Medicine in Phoenix, AZ

Q: What is Gianna Vermeys's NPI number?

The NPI number for Gianna Vermeys is 1235926411. It was assigned to this individual provider in the NPPES registry on April 22, 2025. The provider is also known as Gianna Niemeier MD.

Q: What is Gianna Vermeys's specialty?

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

Q: When was this NPI record last updated?

The NPPES record for Gianna Vermeys was last updated on August 3, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 days 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.

Active since April 22, 2025PECOS Enrolled

5777 E MAYO BLVD, PHOENIX, AZ 85054(480) 342-2000 Get Directions Write a Review

NPPES record last updated: August 3, 2026. Verified against the NPPES registry weekly; last sync: August 09, 2026.

Record update history: Aug 3, 2026, Jun 2, 2026 (2 updates tracked since 2026).

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About Gianna Nicole Niemeier Vermeys Md NPPES

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

GIANNA NICOLE NIEMEIER VERMEYS MD (NPI 1235926411) is an individual internal medicine provider in Phoenix, Arizona, licensed in Arizona (R81706) and active in the NPI registry since April 2025. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1235926411

Entity TypeIndividualFemale

Primary Taxonomy207R00000X

Provider Legal NameGIANNA NICOLE NIEMEIER VERMEYSCredential: MD

Location Address5777 E MAYO BLVDPhoenix, AZ 85054-4502

Mailing AddressPo Box 860912Minneapolis, MN 55486-0912

Phone(480) 342-2000

Sole ProprietorNo

Enumeration DateApril 22, 2025

Last NPPES UpdateAugust 3, 20262 updates tracked since enumeration

NPPES CertifiedAugust 3, 2026

✔ NPI 1235926411 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207R00000X

License✔ Licensed in AZ · R81706

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.

5777 E MAYO BLVD, Phoenix, AZ 85054

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Other Names 1

Former Name (1)Gianna Niemeier Md

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Gianna Nicole Niemeier Vermeys 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.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 85054 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

$127.71 typical visit price

range $55.44 – $168.60

Typical copayment $31.92 (range $13.86 – $42.15)

Most-billed visit code 99204

Established Patient

$98.00 typical visit price

range $17.72 – $137.41

Typical copayment $24.50 (range $4.43 – $34.35)

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.

Other Providers at the Same Location NPPES 20

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

MEAGAN ELIZABETH TIBBO M.D.

Orthopaedic Surgery