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Internal Medicine

Ralph A. Herrera, MD

Sees patients in Stockton, CA · California

Summary

Ralph A. Herrera, MD (Internal Medicine) is enrolled with Medicare at 1 practice location in Stockton, CA. NPI 1306924055. Medicare data says the clinician accepts Medicare assignment. Source: CMS National Downloadable File, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Ralph A. Herrera, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
30Years since medical school (graduated 1996)
Creighton University School Of MedicineMedical school
MaleGender (as listed)
Permanente Medical Group IncGroup practice

Quick answers

Where does Ralph A. Herrera see patients?
Medicare's clinician data lists 1 practice location in Stockton, CA. Call before your visit to confirm the address.
What is Ralph A. Herrera's specialty?
Medicare lists Internal Medicine as the primary specialty, and also Pediatric Medicine.
Does Ralph A. Herrera accept Medicare assignment?
Yes. Medicare's clinician data says Ralph A. Herrera accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for Ralph A. Herrera?
(209) 476-2000, as listed in official Medicare / NPI Registry data.
What is Ralph A. Herrera's NPI number?
1306924055. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Ralph A. Herrera is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Ralph A. Herrera as a member of this group (CMS data updated 2026-10-02).

  • Permanente Medical Group Inc10,996 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in Stockton

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

All internal medicine doctors in Stockton →

Clinician information

CredentialMD
Medical schoolCreighton University School Of Medicine
Graduation year1996
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1306924055
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. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians