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Family Practice

Grace N. Kumamoto, MD

Sees patients in Riverside, CA · California

Summary

Dr. Grace N. Kumamoto, MD is a family doctor at 6405 Day St, Riverside, CA 92507. Phone: (951) 697-5556. Accepts Medicare assignment. In 2024, Grace N. Kumamoto had 215 Original Medicare patients and 1,314 services. NPI 1871578161. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Family doctor (Medicare lists Family Practice)
  • Address: 6405 Day St, Riverside, CA 92507 · Directions (1 more location)
  • Phone: (951) 697‑5556
  • Medicare: Accepts Medicare assignment
  • Group practice: Riverside Medical Clinic Inc
  • Medical school: Loma Linda University School Of Medicine · graduated 1995 (31 years since medical school)
  • Gender (as listed): Female
  • Telehealth: offered

From official Medicare data

This page shows what Medicare's official clinician data says about Grace N. Kumamoto, 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 Grace N. Kumamoto accept Medicare assignment?
Yes. Medicare's clinician data says Grace N. Kumamoto 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 Grace N. Kumamoto see?
In 2024, CMS data shows 215 Original Medicare patients and 1,314 services for Grace N. Kumamoto. This counts Original Medicare only and measures volume, not quality.
What is Grace N. Kumamoto's NPI number?
1871578161. 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 Grace N. Kumamoto, 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 patients215
Services billed to Medicare1,314
Different services or procedures35
Participating Medicare providerYes
Average age of these patients74

Most frequent services

  1. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)201 services
  2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)163 services
  3. Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit (G0439)151 services
  4. Annual depression screening, 5 to 15 minutes (G0444)147 services
  5. Administration of influenza virus vaccine (G0008)14 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 cholesterol75%
  • High blood pressure65%
  • Arthritis39%
  • Diabetes32%
  • Chronic kidney disease25%
  • Osteoporosis18%

Practice locations

Addresses where Grace N. Kumamoto is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Grace N. Kumamoto as a member of this group (CMS data updated October 2, 2026).

  • Riverside Medical Clinic Inc173 clinicians in the group

Specialties

Find other Family Practice doctors in California →

Other family doctors in Riverside

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

All family doctors in Riverside →

Other clinicians in Riverside Medical Clinic Inc

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

Clinician information

CredentialMD
Medical schoolLoma Linda University School Of Medicine
Graduation year1995 (31 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1871578161
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 October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians