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Internal Medicine

Sonali S. Master, MD

Works at hospitals in San Marcos, CA · California

Summary

Sonali S. Master, MD (Internal Medicine) is listed by Medicare at 1 hospital in San Marcos, CA. NPI 1700934783. 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 Sonali S. Master, 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

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
30Years since medical school (graduated 1996)
Northwestern University Feinberg Medical SchoolMedical school
FemaleGender (as listed)
Southern California Permanente Medical GroupGroup practice

Quick answers

Which hospitals does Sonali S. Master work at?
Medicare's official clinician data lists Sonali S. Master at 1 hospital: Kaiser Foundation Hospital - San Marcos. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Sonali S. Master see patients?
Medicare's clinician data lists 3 practice locations, including San Marcos, CA and San Diego, CA. Call before your visit to confirm the address.
What is Sonali S. Master's specialty?
Medicare lists Internal Medicine as the primary specialty, and also Gastroenterology.
Does Sonali S. Master accept Medicare assignment?
Yes. Medicare's clinician data says Sonali S. Master 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 Sonali S. Master?
(833) 574-2273, as listed in official Medicare / NPI Registry data.
What is Sonali S. Master's NPI number?
1700934783. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Sonali S. Master works

Medicare's Facility Affiliation Data lists Sonali S. Master 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 Sonali S. Master is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Sonali S. Master as a member of this group (CMS data updated 2026-10-02).

  • Southern California Permanente Medical Group11,293 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in San Marcos

Clinicians with the same Medicare primary specialty in San Marcos, CA — not a recommendation.

All internal medicine doctors in San Marcos →

Clinician information

CredentialMD
Medical schoolNorthwestern University Feinberg Medical School
Graduation year1996
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1700934783
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