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Gastroenterology

Andrew C. Ko, MD

Works at hospitals in Orange, CA · Seattle, WA · California, Washington

Summary

Andrew C. Ko, MD (Gastroenterology) is listed by Medicare at 2 hospitals in Orange, CA and Seattle, WA. NPI 1437170990. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Andrew C. Ko, 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

GastroenterologyPrimary specialty
YesAccepts Medicare assignment
40Years since medical school (graduated 1986)
R Franklin University Of Med & Sci/chicago Medical SchoolMedical school
MaleGender (as listed)
UC RegentsGroup practice

Quick answers

Which hospitals does Andrew C. Ko work at?
Medicare's official clinician data lists Andrew C. Ko at 2 hospitals: UCI Health-Orange and University of Washington Medical Ctr. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Andrew C. Ko see patients?
Medicare's clinician data lists 1 practice location in Orange, CA. Call before your visit to confirm the address.
What is Andrew C. Ko's specialty?
Medicare lists Gastroenterology as the primary specialty, and also Internal Medicine.
Does Andrew C. Ko accept Medicare assignment?
Yes. Medicare's clinician data says Andrew C. Ko 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 Andrew C. Ko?
(714) 456-7002, as listed in official Medicare / NPI Registry data.
What is Andrew C. Ko's NPI number?
1437170990. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Andrew C. Ko works

Medicare's Facility Affiliation Data lists Andrew C. Ko at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Andrew C. Ko is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Andrew C. Ko as a member of this group (CMS data updated 2026-10-02).

  • UC Regents319 clinicians in the group

Specialties

Find other Gastroenterology doctors in California →

Other gastroenterologists in Orange

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

All gastroenterologists in Orange →

Clinician information

CredentialMD
Medical schoolR Franklin University Of Med & Sci/chicago Medical School
Graduation year1986
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1437170990
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. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  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