ARROYO NEPHROLOGY ASSOCIATES
NPI 1033490453
Internal Medicine - Nephrology in Pasadena, CA

Q: What is Arroyo Nephrology Associates's NPI number?

The NPI number for Arroyo Nephrology Associates is 1033490453. It was assigned to this organization in the NPPES registry on August 30, 2011.

Q: What is Arroyo Nephrology Associates's specialty?

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

Active since August 30, 2011

301 S FAIR OAKS AVE STE 405, PASADENA, CA 91105(626) 794-7075(626) 404-7545 Get Directions Write a Review

NPPES record last updated: March 6, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

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About Arroyo Nephrology Associates NPPES

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

ARROYO NEPHROLOGY ASSOCIATES (NPI 1033490453) is a healthcare organization registered as a nephrology in Pasadena, California and active in the NPI registry since August 2011. The organization lists Ashok Sunder Raj, President, as its authorized official.

NPPES Registry Identity

NPI1033490453

Entity TypeOrganization

Primary Taxonomy207RN0300X

Legal Business NameARROYO NEPHROLOGY ASSOCIATES

Location Address301 S FAIR OAKS AVE STE 405Pasadena, CA 91105-2562

Mailing Address301 S Fair Oaks Ave Ste 405Pasadena, CA 91105-2562 · (626) 794-7075 · Fax (626) 404-7545

Phone(626) 794-7075

Fax(626) 404-7545

Organization SubpartNo

Authorized OfficialAshok Sunder RajPresident · (626) 794-7075

Enumeration DateAugust 30, 2011

Last NPPES UpdateMarch 6, 2026

NPPES CertifiedMarch 6, 2026

✔ NPI 1033490453 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 · A41453

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.

301 S FAIR OAKS AVE STE 405, Pasadena, CA 91105

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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)

Arroyo Nephrology Associates is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 2 clinicians reassign Medicare billing to Arroyo Nephrology Associates, which bills Medicare for the services they deliver. Of these, 2 practice at this address. They are listed nearest first.

Clinicians, nearest first (2)

Ilian Marquez, M.D.

Nephrology

NPI 1710019906

301 S FAIR OAKS AVE STE 405
Pasadena, CA 91105

(626) 794-7075

✔ PECOS✔ Accepts MedicareSame address

Ashok Sunder Raj, M.D.

Nephrology

NPI 1093744070

301 S FAIR OAKS AVE STE 405
Pasadena, CA 91105

(626) 794-7075

✔ PECOS✔ Accepts MedicareSame address

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 Arroyo Nephrology Associates's NPI number?

The NPI number for Arroyo Nephrology Associates is 1033490453. It was assigned to this organization in the NPPES registry on August 30, 2011.

Where is Arroyo Nephrology Associates located?

Arroyo Nephrology Associates is located at 301 S Fair Oaks Ave Ste 405, Pasadena, CA 91105. The listed phone number is (626) 794-7075.

What is Arroyo Nephrology Associates's specialty?

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

Is Arroyo Nephrology Associates enrolled in Medicare?

Yes. Arroyo Nephrology Associates is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Arroyo Nephrology Associates?

According to the CMS Revalidation Reassignment List (October 2026 release), 2 clinicians, all in Nephrology, reassign their Medicare billing to Arroyo Nephrology Associates. 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. Of these, 2 practice at this address. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Arroyo Nephrology Associates was last updated on March 6, 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.