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KATHARINE OZEKI M.D.
NPI 1306290838
Internal Medicine - Gastroenterology in Walnut Creek, CA

Active since April 21, 2016PECOS EnrolledAccepts Medicare Assignment
1425 S MAIN ST, WALNUT CREEK, CA 94596(925) 295-4080 Get Directions Write a Review

NPPES record last updated: July 26, 2023. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Katharine Ozeki M.d. NPPES

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

KATHARINE OZEKI M.D. (NPI 1306290838) is an individual gastroenterology provider in Walnut Creek, California, licensed in California (A151141) and active in the NPI registry since April 2016. She is enrolled in Medicare PECOS and is a graduate of University Of Southern California Keck School Of Medicine (2016).

NPPES Registry Identity

NPI1306290838
Entity TypeIndividualFemale
Primary Taxonomy207RG0100X
Provider Legal NameKATHARINE OZEKICredential: M.D.
Location Address1425 S MAIN STWalnut Creek, CA 94596-5318
Mailing Address1425 S Main StWalnut Creek, CA 94596-5318 · (925) 295-4080
Phone(925) 295-4080
Sole ProprietorYes
Medical School CMSUniversity Of Southern California Keck School Of MedicineGraduated 2016
Enumeration DateApril 21, 2016
Last NPPES UpdateJuly 26, 2023
NPPES CertifiedJuly 25, 2023
✔ NPI 1306290838 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians
Taxonomy Code207RG0100X
License✔ Licensed in CA · A151141
Definition
An internist who specializes in diagnosis and treatment of diseases of the digestive organs including the stomach, bowels, liver and gallbladder. This specialist treats conditions such as abdominal pain, ulcers, diarrhea, cancer and jaundice and performs complex diagnostic and therapeutic procedures using endoscopes to visualize internal organs.
Also ListedStudent in an Organized Health Care Education/Training ProgramTaxonomy 390200000X
1425 S MAIN ST, Walnut Creek, CA 94596
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Katharine Ozeki M.d. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID1557697893
PECOS Enrollment IDI20190724004057
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency– Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Katharine Ozeki reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Permanente Medical Group Inc
17 mi
Internal Medicine
901 NEVIN
Richmond, CA 94801
  • Reassigned Medicare billing, California enrollment
  • 20,078 clinicians in this Medicare group
NPI 1235226531 (510) 307-1555

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

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94596 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$153.83 typical visit price
range $69.00 – $202.35
Typical copayment $38.45 (range $17.25 – $50.58)
Most-billed visit code 99204
Established Patient
$119.48 typical visit price
range $23.44 – $166.46
Typical copayment $29.87 (range $5.86 – $41.61)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

BROOK ANDREW WOOLLEY M.D.
Emergency Medicine
1425 S MAIN ST, EMERGENCY MEDICINE DEPARTMENT
WALNUT CREEK, CA 94596
Contra Costa County (925) 295-5100
DR. THOMAS CRESANTE D.O.
Hospitalist
1425 S MAIN ST, KAISER PERMANENTE WALNUT CREEK ATTN: HBS DEPT
WALNUT CREEK, CA 94596
Contra Costa County (925) 295-4643
SARA WON MD
Obstetrics & Gynecology
1425 S MAIN ST
WALNUT CREEK, CA 94596
Contra Costa County (925) 295-4040
KAISER PERMANENTE
General Acute Care Hospital
1425 S MAIN ST
WALNUT CREEK, CA 94596
Contra Costa County (925) 295-4000
MICHELLE CABLE VU CRNA
Nurse Anesthetist, Certified Registered
1425 S MAIN ST
WALNUT CREEK, CA 94596
Contra Costa County (925) 295-4000
DR. JESUS GIL JIMENEZ MD
Surgery (Vascular Surgery)
1425 S MAIN ST
WALNUT CREEK, CA 94596
Contra Costa County (925) 295-4110
MR. EDWARD HAL PIECZENIK L.C.S.W.
Social Worker (Clinical)
1425 S MAIN ST
WALNUT CREEK, CA 94596
Contra Costa County (925) 295-5237
CARLOS A. CROMEYER MD
Psychiatry & Neurology (Neurology)
1425 S MAIN ST
WALNUT CREEK, CA 94596
Contra Costa County (925) 295-4000

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 Katharine Ozeki's NPI number?

The NPI number for Katharine Ozeki is 1306290838. It was assigned to this individual provider in the NPPES registry on April 21, 2016.

Where is Katharine Ozeki located?

Katharine Ozeki practices at 1425 S Main St, Walnut Creek, CA 94596. The listed phone number is (925) 295-4080.

What is Katharine Ozeki's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Is Katharine Ozeki enrolled in Medicare?

Yes. Katharine Ozeki is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organization bills Medicare for Katharine Ozeki's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Katharine Ozeki reassigns Medicare benefits to Permanente Medical Group Inc (Richmond, CA). The 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 Katharine Ozeki's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Katharine Ozeki was last updated on July 26, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 years 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.