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Internal Medicine

Matthew P. Mesias, MD

Works at hospitals in Burlingame, CA · Stanford, CA · California

Summary

Dr. Matthew P. Mesias, MD is an internal medicine doctor at 300 Pasteur Dr, Stanford, CA 94305. Phone: (650) 723-4000. Accepts Medicare assignment. In 2024, Matthew P. Mesias had 186 Original Medicare patients and 446 services. NPI 1467792721. 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: 300 Pasteur Dr, Stanford, CA 94305 · Directions
  • Phone: (650) 723‑4000
  • Medicare: Accepts Medicare assignment
  • Hospitals: Peninsula Medical Center, Stanford Health Care
  • Group practice: Stanford Health Care
  • Medical school: Johns Hopkins University School Of Medicine · graduated 2014 (12 years since medical school)
  • Gender (as listed): Male
  • Telehealth: offered

From official Medicare data

This page shows what Medicare's official clinician data says about Matthew P. Mesias, 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 Matthew P. Mesias accept Medicare assignment?
Yes. Medicare's clinician data says Matthew P. Mesias 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 Matthew P. Mesias see?
In 2024, CMS data shows 186 Original Medicare patients and 446 services for Matthew P. Mesias. This counts Original Medicare only and measures volume, not quality.
What is Matthew P. Mesias's NPI number?
1467792721. 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 Matthew P. Mesias, 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 patients186
Services billed to Medicare446
Different services or procedures19
Participating Medicare providerYes
Average age of these patients86

Most frequent services

  1. Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more (99215)93 services
  2. Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's (G2211)91 services
  3. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)81 services
  4. Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit (G0439)51 services
  5. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)24 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 cholesterol59%
  • Arthritis50%
  • Alzheimer's disease or dementia47%
  • Chronic kidney disease37%
  • Ischemic heart disease35%

Hospitals where Matthew P. Mesias works

Medicare's Facility Affiliation Data lists Matthew P. Mesias 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.

  • Peninsula Medical CenterBurlingame, CA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 050007
  • Stanford Health CareStanford, CA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 050441

Practice locations

Addresses where Matthew P. Mesias is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Matthew P. Mesias as a member of this group (CMS data updated October 2, 2026).

  • Stanford Health Care3,122 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in Stanford

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

All internal medicine doctors in Stanford →

Other clinicians in Stanford Health Care

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

Clinician information

CredentialMD
Medical schoolJohns Hopkins University School Of Medicine
Graduation year2014 (12 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1467792721
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