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Emergency Medicine

Lonnie Seo, MD

Works at hospitals in Stamford, CT · Connecticut

Summary

Lonnie Seo, MD (Emergency Medicine) is listed by Medicare at 1 hospital in Stamford, CT. NPI 1740785211. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Lonnie Seo, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Emergency MedicinePrimary specialty
YesAccepts Medicare assignment
8Years since medical school (graduated 2018)
FemaleGender (as listed)
Emergency Medicine Physicians of Fairfield County LLCGroup practice

Quick answers

Which hospitals does Lonnie Seo work at?
Medicare's official clinician data lists Lonnie Seo at 1 hospital: Stamford Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Lonnie Seo see patients?
Medicare's clinician data lists 1 practice location in Stamford, CT. Call before your visit to confirm the address.
What is Lonnie Seo's specialty?
Medicare lists Emergency Medicine as the primary specialty.
Does Lonnie Seo accept Medicare assignment?
Yes. Medicare's clinician data says Lonnie Seo accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for Lonnie Seo?
(203) 276-4925, as listed in official Medicare / NPI Registry data.
What is Lonnie Seo's NPI number?
1740785211. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Lonnie Seo works

Medicare's Facility Affiliation Data lists Lonnie Seo at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Lonnie Seo is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Lonnie Seo as a member of this group (CMS data updated 2026-10-02).

  • Emergency Medicine Physicians of Fairfield County LLC35 clinicians in the group

Specialties

Find other Emergency Medicine doctors in Connecticut →

Other emergency medicine doctors in Stamford

Clinicians with the same Medicare primary specialty in Stamford, CT — not a recommendation.

All emergency medicine doctors in Stamford →

Clinician information

CredentialMD
Graduation year2018
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1740785211
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. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  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