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Otolaryngology

Marietta Tan, MD

Sees patients in Largo, MD · Woodbridge, VA · Halethorpe, MD … · Maryland, Virginia

Summary

Dr. Marietta Tan, MD is an ENT doctor at 1221 Mercantile Ln, Largo, MD 20774. Phone: (301) 618-5700. Accepts Medicare assignment. In 2024, Marietta Tan had 13 Original Medicare patients and 32 services. NPI 1932342698. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: ENT doctor (Medicare lists Otolaryngology)
  • Address: 1221 Mercantile Ln, Largo, MD 20774 · Directions (4 more locations)
  • Phone: (301) 618‑5700
  • Medicare: Accepts Medicare assignment
  • Group practice: Kaiser Foundation Health Plan of the Mid Atlantic States, Inc
  • Medical school: Johns Hopkins University School Of Medicine · graduated 2009 (17 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Marietta Tan, 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 Marietta Tan accept Medicare assignment?
Yes. Medicare's clinician data says Marietta Tan 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 Marietta Tan see?
In 2024, CMS data shows 13 Original Medicare patients and 32 services for Marietta Tan. This counts Original Medicare only and measures volume, not quality.
What is Marietta Tan's NPI number?
1932342698. 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 Marietta Tan, 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 Medicare32
Different services or procedures12
Participating Medicare providerYes
Average age of these patients73

Practice locations

Addresses where Marietta Tan is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Marietta Tan as a member of this group (CMS data updated October 2, 2026).

  • Kaiser Foundation Health Plan of the Mid Atlantic States, Inc1,899 clinicians in the group

Specialties

Find other Otolaryngology doctors in Maryland →

Other ENT doctors in Largo

Clinicians with the same Medicare primary specialty in Largo, MD — not a recommendation.

All ENT doctors in Largo →

Other clinicians in Kaiser Foundation Health Plan of the Mid Atlantic States, Inc

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

Clinician information

CredentialMD
Medical schoolJohns Hopkins University School Of Medicine
Graduation year2009 (17 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1932342698
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