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Psychiatry

William M. Irvin Jr., MD

Works at hospitals in Saint Louis, MO · Missouri

Summary

Dr. William M. Irvin Jr., MD is a psychiatrist at 1015 Bowles Ave, Fenton, MO 63026. Phone: (636) 496-2000. Accepts Medicare assignment. In 2024, William M. Irvin Jr. had 62 Original Medicare patients and 477 services. NPI 1942392931. 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: Psychiatrist (Medicare lists Psychiatry)
  • Address: 1015 Bowles Ave, Fenton, MO 63026 · Directions (1 more location)
  • Phone: (636) 496‑2000
  • Medicare: Accepts Medicare assignment
  • Hospital: SSM Health St Mary's Hospital - St Louis
  • Group practice: SSM Health Care St Louis
  • Medical school: Saint Louis University School Of Medicine · graduated 1997 (29 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 William M. Irvin Jr., 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. Irvin Jr. accept Medicare assignment?
Yes. Medicare's clinician data says William M. Irvin Jr. 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. Irvin Jr. see?
In 2024, CMS data shows 62 Original Medicare patients and 477 services for William M. Irvin Jr.. This counts Original Medicare only and measures volume, not quality.
What is William M. Irvin Jr.'s NPI number?
1942392931. 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. Irvin Jr., 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 patients62
Services billed to Medicare477
Different services or procedures11
Participating Medicare providerYes
Average age of these patients66

Most frequent services

  1. Psychotherapy with evaluation and management visit, 30 minutes (90833)168 services
  2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)117 services
  3. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)64 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%
  • Depression75%
  • Anxiety68%
  • Arthritis52%
  • Diabetes35%

Hospitals where William M. Irvin Jr. works

Medicare's Facility Affiliation Data lists William M. Irvin Jr. 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 William M. Irvin Jr. is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists William M. Irvin Jr. as a member of this group (CMS data updated October 2, 2026).

  • SSM Health Care St Louis167 clinicians in the group

Specialties

Find other Psychiatry doctors in Missouri →

Other psychiatrists in Missouri

Clinicians with the same Medicare primary specialty in Missouri — not a recommendation.

All psychiatrists in Missouri →

Other clinicians in SSM Health Care St Louis

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

Clinician information

CredentialMD
Medical schoolSaint Louis University School Of Medicine
Graduation year1997 (29 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1942392931
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