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Internal Medicine

Charlotte J. Bai, MD

Works at hospitals in South San Francisco, CA · California

Summary

Dr. Charlotte J. Bai, MD is an internal medicine doctor at 1200 El Camino Real, South San Francisco, CA 94080. Phone: (650) 742-2000. Accepts Medicare assignment. In 2024, Charlotte J. Bai had 66 Original Medicare patients and 93 services. NPI 1740484807. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Internal medicine doctor (Medicare lists Internal Medicine)
  • Address: 1200 El Camino Real, South San Francisco, CA 94080 · Directions
  • Phone: (650) 742‑2000
  • Medicare: Accepts Medicare assignment
  • Hospital: Kaiser Foundation Hospital - South San Francisco
  • Group practice: Permanente Medical Group Inc
  • Medical school: Northeastern Ohio University College Of Medicine · graduated 2001 (25 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Charlotte J. Bai, 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 Charlotte J. Bai accept Medicare assignment?
Yes. Medicare's clinician data says Charlotte J. Bai 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 Charlotte J. Bai see?
In 2024, CMS data shows 66 Original Medicare patients and 93 services for Charlotte J. Bai. This counts Original Medicare only and measures volume, not quality.
What is Charlotte J. Bai's NPI number?
1740484807. 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 Charlotte J. Bai, 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 patients66
Services billed to Medicare93
Different services or procedures11
Participating Medicare providerYes
Average age of these patients73

Most frequent services

  1. Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only (93010)51 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol67%
  • Diabetes56%
  • Chronic kidney disease44%
  • Heart failure44%
  • Ischemic heart disease39%

Hospitals where Charlotte J. Bai works

Medicare's Facility Affiliation Data lists Charlotte J. Bai at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

Practice locations

Addresses where Charlotte J. Bai is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Charlotte J. Bai as a member of this group (CMS data updated October 2, 2026).

  • Permanente Medical Group Inc10,996 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in South San Francisco

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

All internal medicine doctors in South San Francisco →

Other clinicians in Permanente Medical Group Inc

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

Clinician information

CredentialMD
Medical schoolNortheastern Ohio University College Of Medicine
Graduation year2001 (25 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1740484807
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 October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians