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Obstetrics/Gynecology

Fernando T. Mariz, MD

Sees patients in New York, NY · New York

Summary

Dr. Fernando T. Mariz, MD is an OB-GYN at 18 E 41st St, Fl 2, New York, NY 10017. Phone: (646) 290-9560. Accepts Medicare assignment. In 2024, Fernando T. Mariz had 13 Original Medicare patients and 130 services. NPI 1043619273. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: OB-GYN (Medicare lists Obstetrics/Gynecology)
  • Address: 18 E 41st St, Fl 2, New York, NY 10017 · Directions (1 more location)
  • Phone: (646) 290‑9560
  • Medicare: Accepts Medicare assignment
  • Group practice: Maiden Lane Medical PLLC
  • Medical school: graduated 2014 (12 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Fernando T. Mariz, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Fernando T. Mariz accept Medicare assignment?
Yes. Medicare's clinician data says Fernando T. Mariz accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Fernando T. Mariz see?
In 2024, CMS data shows 13 Original Medicare patients and 130 services for Fernando T. Mariz. This counts Original Medicare only and measures volume, not quality.
What is Fernando T. Mariz's NPI number?
1043619273. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Fernando T. Mariz, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients13
Services billed to Medicare130
Different services or procedures22
Participating Medicare providerYes
Average age of these patients68

Practice locations

Addresses where Fernando T. Mariz is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Fernando T. Mariz as a member of this group (CMS data updated October 2, 2026).

  • Maiden Lane Medical PLLC19 clinicians in the group

Specialties

Find other Obstetrics/Gynecology doctors in New York →

Other OB-GYNs in New York

Clinicians with the same Medicare primary specialty in New York, NY — not a recommendation.

All OB-GYNs in New York →

Other clinicians in Maiden Lane Medical PLLC

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Graduation year2014 (12 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1043619273
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians