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JOHN A RITZO MD MEDICAL CORPORATION
NPI 1427948264
Family Medicine in San Mateo, CA

Active since July 03, 2025
101 S SAN MATEO DR STE 206, SAN MATEO, CA 94401(650) 343-4003(650) 696-7040 Get Directions Write a Review

NPPES record last updated: July 3, 2025. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About John A Ritzo Md Medical Corporation NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

JOHN A RITZO MD MEDICAL CORPORATION (NPI 1427948264) is a healthcare organization registered as a family medicine in San Mateo, California and active in the NPI registry since July 2025. The organization lists Johna A Ritzo, Physician / Owner, as its authorized official.

NPPES Registry Identity

NPI1427948264
Entity TypeOrganization
Primary Taxonomy207Q00000X
Legal Business NameJOHN A RITZO MD MEDICAL CORPORATION
Location Address101 S SAN MATEO DR STE 206San Mateo, CA 94401-3843
Mailing Address101 S San Mateo Dr Ste 206San Mateo, CA 94401-3843 · (650) 343-4003 · Fax (650) 696-7040
Phone(650) 343-4003
Fax(650) 696-7040
Organization SubpartNo
Authorized OfficialJohna A RitzoPhysician / Owner · (650) 533-7211
Enumeration DateJuly 3, 2025
NPPES CertifiedJuly 3, 2025
✔ NPI 1427948264 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyFamily MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207Q00000X
Definition
Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadth which integrates the biological, clinical, and behavioral sciences. The scope of family medicine is not limited by age, sex, organ system, or disease entity.
101 S SAN MATEO DR STE 206, San Mateo, CA 94401
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Group Practice 1

Group TaxonomyThis provider is a business group of one or more individual practitioners, who practice with different areas of specialization.193200000X MULTI-SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

John A Ritzo Md Medical Corporation is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 1 clinician reassigns Medicare billing to John A Ritzo MD Medical Corporation, which bills Medicare for the services this clinician delivers.

Clinician (1)

John Ritzo, MD
Family Practice
NPI 1326780115
76 HIGH ST
Lewiston, ME 04240
(207) 795-2800
✔ PECOS✔ Accepts Medicare2,722 mi

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is John A Ritzo MD Medical Corporation's NPI number?

The NPI number for John A Ritzo MD Medical Corporation is 1427948264. It was assigned to this organization in the NPPES registry on July 3, 2025.

Where is John A Ritzo MD Medical Corporation located?

John A Ritzo MD Medical Corporation is located at 101 S San Mateo Dr Ste 206, San Mateo, CA 94401. The listed phone number is (650) 343-4003.

What is John A Ritzo MD Medical Corporation's specialty?

The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.

Is John A Ritzo MD Medical Corporation enrolled in Medicare?

Yes. John A Ritzo MD Medical Corporation is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through John A Ritzo MD Medical Corporation?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Family Practice) reassigns their Medicare billing to John A Ritzo MD Medical Corporation. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for John A Ritzo MD Medical Corporation was last updated on July 3, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 15 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.