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THUYVAN LAM NGUYEN D.O.
NPI 1275859233
Internal Medicine in Riverside, CA

Active since April 15, 2010PECOS Enrolled
2799 GATEWAY DR STE 100, RIVERSIDE, CA 92507(833) 450-5967(833) 450-5967 Get Directions Write a Review

NPPES record last updated: July 29, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Jul 29, 2026, Jul 17, 2026, Sep 28, 2015 (3 updates tracked since 2015).

About Thuyvan Lam Nguyen D.o. NPPES

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

THUYVAN LAM NGUYEN D.O. (NPI 1275859233) is an individual internal medicine provider in Riverside, California, licensed in California (20A11905) and active in the NPI registry since April 2010. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1275859233
Entity TypeIndividualFemale
Primary Taxonomy207R00000X
Provider Legal NameTHUYVAN LAM NGUYENCredential: D.O.
Location Address2799 GATEWAY DR STE 100Riverside, CA 92507-0908
Mailing Address2799 Gateway Dr Ste 100Riverside, CA 92507-0908 · (833) 450-5967 · Fax (833) 450-5967
Phone(833) 450-5967
Fax(833) 450-5967
Sole ProprietorNo
Enumeration DateApril 15, 2010
Last NPPES UpdateJuly 29, 20263 updates tracked since enumeration
NPPES CertifiedJuly 29, 2026
✔ NPI 1275859233 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in CA · 20A11905
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
2799 GATEWAY DR STE 100, Riverside, CA 92507
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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 (PECOS)

Thuyvan Lam Nguyen D.o. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

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 Reassignments

5

Medicare enrollment records show Thuyvan Nguyen reassigns Medicare billing to 5 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Beaver Medical Group P C
9.3 mi
Family Medicine
2 WEST FERN AVENUE
Redlands, CA 92373
  • Reassigned Medicare billing, California enrollment
  • 635 clinicians in this Medicare group
NPI 1649503319 (909) 793-3311
Pinnacle Medical Group, Inc
15 mi
Family Medicine
8110 MANGO AVE
Fontana, CA 92335
  • Reassigned Medicare billing, California enrollment
  • 149 clinicians in this Medicare group
NPI 1376876912 (909) 427-1303
Saddleback Medical Group Inc
33 mi
Gastroenterology
24221 CALLE DE LA LOUISA, SUITE 400
Laguna Hills, CA 92653
  • Reassigned Medicare billing, California enrollment
  • 86 clinicians in this Medicare group
NPI 1386605822 (949) 465-8155
Healthcare Partners Affiliates Medical Group
34 mi
Addiction Medicine
14591 NEWPORT AVE
Tustin, CA 92780
  • Reassigned Medicare billing, California enrollment
  • 2,052 clinicians in this Medicare group
NPI 1891981502 (714) 442-4864
Centers For Family Medicine Gp
46 mi
Family Medicine
3460 KATELLA AVE
Los Alamitos, CA 90720
  • Reassigned Medicare billing, California enrollment
  • 228 clinicians in this Medicare group
NPI 1467598243 (562) 594-6599

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 92507 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
$136.04 typical visit price
range $59.60 – $179.42
Typical copayment $34.01 (range $14.90 – $44.85)
Most-billed visit code 99204
Established Patient
$104.64 typical visit price
range $19.37 – $146.42
Typical copayment $26.16 (range $4.84 – $36.60)
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 3

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

FELIPE MENDEZ CENDEJAS PA-C
Physician Assistant (Medical)
2799 GATEWAY DR STE 100
RIVERSIDE, CA 92507
Riverside County (888) 530-4415
GEIA SOTTO DAVIS NP-C
Nurse Practitioner (Family)
2799 GATEWAY DR STE 100
RIVERSIDE, CA 92507
Riverside County (833) 450-5957
MS. MADHU FRANCY NP
Nurse Practitioner (Family)
2799 GATEWAY DR STE 100
RIVERSIDE, CA 92507
Riverside County (888) 530-4415

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 Thuyvan Nguyen's NPI number?

The NPI number for Thuyvan Nguyen is 1275859233. It was assigned to this individual provider in the NPPES registry on April 15, 2010.

Where is Thuyvan Nguyen located?

Thuyvan Nguyen practices at 2799 Gateway Dr Ste 100, Riverside, CA 92507. The listed phone number is (833) 450-5967.

What is Thuyvan Nguyen's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Thuyvan Nguyen enrolled in Medicare?

Yes. Thuyvan Nguyen is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Thuyvan Nguyen's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Thuyvan Nguyen reassigns Medicare benefits to 5 organizations: Beaver Medical Group P C (Redlands, CA), Pinnacle Medical Group, Inc (Fontana, CA), Saddleback Medical Group Inc (Laguna Hills, CA), Healthcare Partners Affiliates Medical Group (Tustin, CA) and Centers For Family Medicine Gp (Los Alamitos, CA). Each 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 Thuyvan Nguyen'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 Thuyvan Nguyen was last updated on July 29, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.