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ANDREA TIENG, MD INC
NPI 1013276575
Internal Medicine - Gastroenterology in Rancho Cucamonga, CA

Active since May 03, 2012
8283 GROVE AVE STE 206, RANCHO CUCAMONGA, CA 91730(909) 255-7200(909) 255-7215 Get Directions Write a Review

NPPES record last updated: July 4, 2026. Verified against the NPPES registry weekly; last sync: November 01, 2026.

Record update history: Jan 25, 2022, Jun 12, 2018 (2 updates tracked since 2018).

About Andrea Tieng, Md Inc NPPES

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

ANDREA TIENG, MD INC (NPI 1013276575) is a healthcare organization registered as a gastroenterology in Rancho Cucamonga, California and active in the NPI registry since May 2012. The organization lists Andrea S. Tieng, Md, as its authorized official.

NPPES Registry Identity

NPI1013276575
Entity TypeOrganization
Primary Taxonomy207RG0100X
Legal Business NameANDREA TIENG, MD INC
Location Address8283 GROVE AVE STE 206Rancho Cucamonga, CA 91730-3141
Mailing Address8283 Grove Ave Ste 206Rancho Cucamonga, CA 91730-3141 · (909) 255-7200 · Fax (909) 255-7215
Phone(909) 255-7200
Fax(909) 255-7215
Organization SubpartNo
Authorized OfficialAndrea S. TiengMd · (909) 255-7200
Enumeration DateMay 3, 2012
Last NPPES UpdateJuly 4, 20262 updates tracked since enumeration
NPPES CertifiedJuly 4, 2026
✔ NPI 1013276575 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians
Taxonomy Code207RG0100X
License✔ Licensed in CA · A106477
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.
8283 GROVE AVE STE 206, Rancho Cucamonga, CA 91730
Open in Google Maps ↗

Other Identifiers 1

Other1356528566Personal Npi

Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Andrea Tieng, Md Inc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 1 clinician reassigns Medicare billing to Andrea Tieng, MD Inc, which bills Medicare for the services this clinician delivers.

Clinician (1)

Andrea Tieng, M.D.
Gastroenterology
NPI 1356528566
10801 FOOTHILL BLVD STE 106
Rancho Cucamonga, CA 91730
(909) 255-7200
✔ PECOS✔ Accepts Medicare3.4 mi

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

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 Andrea Tieng, MD Inc's NPI number?

The NPI number for Andrea Tieng, MD Inc is 1013276575. It was assigned to this organization in the NPPES registry on May 3, 2012.

Where is Andrea Tieng, MD Inc located?

Andrea Tieng, MD Inc is located at 8283 Grove Ave Ste 206, Rancho Cucamonga, CA 91730. The listed phone number is (909) 255-7200.

What is Andrea Tieng, MD Inc's specialty?

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

Is Andrea Tieng, MD Inc enrolled in Medicare?

Yes. Andrea Tieng, MD Inc is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Andrea Tieng, MD Inc?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Gastroenterology) reassigns their Medicare billing to Andrea Tieng, MD Inc. A 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 the clinician's services. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Andrea Tieng, MD Inc was last updated on July 4, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.