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Hospitalist

William M. Mundy, MD

Works at hospitals in Greenbrae, CA · Lakeport, CA · California

Summary

Dr. William M. Mundy, MD is a hospitalist at 250 Bon Air Rd, Greenbrae, CA 94904. Phone: (415) 925-7000. Accepts Medicare assignment. In 2024, William M. Mundy had 484 Original Medicare patients and 1,374 services. NPI 1336341825. 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: Hospitalist
  • Address: 250 Bon Air Rd, Greenbrae, CA 94904 · Directions (1 more location)
  • Phone: (415) 925‑7000
  • Medicare: Accepts Medicare assignment
  • Hospitals: Marinhealth Medical Center, Sutter Lakeside Hospital
  • Group practice: Galen Inpatient Physicians PC (+1 more)
  • Medical school: Medical College Of Ohio · graduated 1999 (27 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about William M. Mundy, 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 William M. Mundy accept Medicare assignment?
Yes. Medicare's clinician data says William M. Mundy 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 William M. Mundy see?
In 2024, CMS data shows 484 Original Medicare patients and 1,374 services for William M. Mundy. This counts Original Medicare only and measures volume, not quality.
What is William M. Mundy's NPI number?
1336341825. 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 William M. Mundy, 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 patients484
Services billed to Medicare1,374
Different services or procedures8
Participating Medicare providerYes
Average age of these patients79

Most frequent services

  1. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)434 services
  2. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes (99233)420 services
  3. Hospital discharge day management, more than 30 minutes (99239)309 services
  4. Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)129 services
  5. Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes (99231)44 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 cholesterol75%
  • Arthritis56%
  • Chronic kidney disease48%
  • Ischemic heart disease45%
  • Depression39%

Hospitals where William M. Mundy works

Medicare's Facility Affiliation Data lists William M. Mundy 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.

  • Marinhealth Medical CenterGreenbrae, CA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 050360
  • Sutter Lakeside HospitalLakeport, CA · Critical Access Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 051329

Practice locations

Addresses where William M. Mundy is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists William M. Mundy as a member of these groups (CMS data updated October 2, 2026).

  • Galen Inpatient Physicians PC1,077 clinicians in the group
  • Farallon Inpatient Medical Group Inc9 clinicians in the group

Specialties

Find other Hospitalist doctors in California →

Other hospitalists in Greenbrae

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

All hospitalists in Greenbrae →

Other clinicians in Galen Inpatient Physicians PC

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

Clinician information

CredentialMD
Medical schoolMedical College Of Ohio
Graduation year1999 (27 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1336341825
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