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JOHN CHRISTIAN ONG DO
NPI 1477056406
Internal Medicine - Nephrology in Fountain Valley, CA

Active since March 15, 2018PECOS EnrolledAccepts Medicare Assignment
11100 WARNER AVE STE 218, FOUNTAIN VALLEY, CA 92708(714) 641-9696(714) 641-1211 Get Directions Write a Review

NPPES record last updated: January 16, 2026. Verified against the NPPES registry weekly; last sync: August 16, 2026.

Record update history: Jan 16, 2026, Jun 9, 2025, Nov 19, 2024 and 3 more (6 updates tracked since 2018).

About John Christian Ong Do NPPES

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

JOHN CHRISTIAN ONG DO (NPI 1477056406) is an individual nephrology provider in Fountain Valley, California, licensed in California (20A21125) and active in the NPI registry since March 2018. He is enrolled in Medicare PECOS and is a graduate of Other (2020).

NPPES Registry Identity

NPI1477056406
Entity TypeIndividualMale
Primary Taxonomy207RN0300X
Provider Legal NameJOHN CHRISTIAN ONGCredential: DO
Location Address11100 WARNER AVE STE 218Fountain Valley, CA 92708-7511
Mailing Address9373 Hazard Way Ste 200San Diego, CA 92123-1226 · (588) 810-8000 · Fax (858) 268-1911
Phone(714) 641-9696
Fax(714) 641-1211
Sole ProprietorNo
Medical School CMSOtherGraduated 2020
Enumeration DateMarch 15, 2018
Last NPPES UpdateJanuary 16, 20266 updates tracked since enumeration
NPPES CertifiedJanuary 16, 2026
✔ NPI 1477056406 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · NephrologyAllopathic & Osteopathic Physicians
Taxonomy Code207RN0300X
License✔ Licensed in CA · 20A21125
Definition
An internist who treats disorders of the kidney, high blood pressure, fluid and mineral balance and dialysis of body wastes when the kidneys do not function. This specialist consults with surgeons about kidney transplantation.
11100 WARNER AVE STE 218, Fountain Valley, CA 92708
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

John Christian Ong Do 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 ID9638593916
PECOS Enrollment IDI20250813002709
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.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 92708 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
$142.39 typical visit price
range $62.96 – $187.60
Typical copayment $35.59 (range $15.74 – $46.90)
Most-billed visit code 99204
Established Patient
$109.96 typical visit price
range $20.84 – $153.61
Typical copayment $27.49 (range $5.21 – $38.40)
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 8

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

DR. SITHU LIN M.D.
Internal Medicine (Nephrology)
11100 WARNER AVE STE 218
FOUNTAIN VALLEY, CA 92708
Orange County (714) 641-9696
THANH CAO D.O.
Internal Medicine (Nephrology)
11100 WARNER AVE STE 218
FOUNTAIN VALLEY, CA 92708
Orange County (714) 641-9696
DR. NASIM SHAHBAZI MD
Internal Medicine (Nephrology)
11100 WARNER AVE STE 218
FOUNTAIN VALLEY, CA 92708
Orange County (714) 641-9696
ALAN ARTHUR SUSA CANTILLEP MD
Internal Medicine (Nephrology)
11100 WARNER AVE STE 218
FOUNTAIN VALLEY, CA 92708
Orange County (714) 641-9696
RALLABHANDI SANKARAM M.D.
Internal Medicine (Nephrology)
11100 WARNER AVE STE 218
FOUNTAIN VALLEY, CA 92708
Orange County (714) 641-9696
DR. SANDEEP SINGH DANG M.D.
Internal Medicine (Nephrology)
11100 WARNER AVE STE 218
FOUNTAIN VALLEY, CA 92708
Orange County (714) 641-9696
MICHAEL JOSEPH FLOIED P.A.C.
Physician Assistant
11100 WARNER AVE STE 218
FOUNTAIN VALLEY, CA 92708
Orange County (714) 641-9696
BICH THU THI NGUYEN
Nurse Practitioner
11100 WARNER AVE STE 218
FOUNTAIN VALLEY, CA 92708
Orange County (714) 641-9696

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 Ong's NPI number?

The NPI number for John Ong is 1477056406. It was assigned to this individual provider in the NPPES registry on March 15, 2018.

Where is John Ong located?

John Ong practices at 11100 Warner Ave Ste 218, Fountain Valley, CA 92708. The listed phone number is (714) 641-9696.

What is John Ong's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Nephrology, with taxonomy code 207RN0300X.

Is John Ong enrolled in Medicare?

Yes. John Ong 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.

When was this NPI record last updated?

The NPPES record for John Ong was last updated on January 16, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 7 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.