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ALEXANDER F CASTELLANOS MD
NPI 1831260520
Family Medicine in Templeton, CA

Active since November 13, 2006
699 S MAIN ST, STE A, TEMPLETON, CA 93465(805) 434-1804(805) 434-1855 Get Directions Write a Review

NPPES record last updated: February 5, 2020. Verified against the NPPES registry weekly; last sync: November 01, 2026.

Record update history: Feb 5, 2020, Jan 15, 2020 (2 updates tracked since 2020).

About Alexander F Castellanos Md NPPES

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

ALEXANDER F CASTELLANOS MD (NPI 1831260520) is a healthcare organization registered as a family medicine in Templeton, California and active in the NPI registry since November 2006. The organization lists Alexander F Castellanos, President, as its authorized official.

NPPES Registry Identity

NPI1831260520
Entity TypeOrganization
Primary Taxonomy207Q00000X
Legal Business NameALEXANDER F CASTELLANOS MD INC
Location Address699 S MAIN ST, STE ATempleton, CA 93465-5103
Mailing Address699 S Main St, Ste ATempleton, CA 93465-5103 · (805) 434-1804 · Fax (805) 434-1855
Phone(805) 434-1804
Fax(805) 434-1855
Organization SubpartNo
Authorized OfficialAlexander F CastellanosPresident · (805) 434-1804
Enumeration DateNovember 13, 2006
Last NPPES UpdateFebruary 5, 20202 updates tracked since enumeration
✔ NPI 1831260520 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyFamily MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207Q00000X
License✔ Licensed in CA · G37303
Definition
Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadth which integrates the biological, clinical, and behavioral sciences. The scope of family medicine is not limited by age, sex, organ system, or disease entity.
699 S MAIN ST, Templeton, CA 93465
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Other Names 1

Other NameAlexander F Castellanos Md

Other Identifiers 1

Medicaid00G373030CA

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)

Alexander F Castellanos Md 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 Alexander F Castellanos MD, which bills Medicare for the services this clinician delivers.

Clinician (1)

Alexander Castellanos, MD
Family Practice
NPI 1770771511
699 S MAIN ST
Templeton, CA 93465
(805) 434-1804
✔ 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 Alexander F Castellanos MD Inc's NPI number?

The NPI number for Alexander F Castellanos MD Inc is 1831260520. It was assigned to this organization in the NPPES registry on November 13, 2006. The provider is also known as Alexander F Castellanos MD.

Where is Alexander F Castellanos MD Inc located?

Alexander F Castellanos MD Inc is located at 699 S Main St Ste A, Templeton, CA 93465. The listed phone number is (805) 434-1804.

What is Alexander F Castellanos MD Inc's specialty?

The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.

Is Alexander F Castellanos MD Inc enrolled in Medicare?

Yes. Alexander F Castellanos MD Inc is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Alexander F Castellanos MD Inc?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Family Practice) reassigns their Medicare billing to Alexander F Castellanos 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 Alexander F Castellanos MD Inc was last updated on February 5, 2020. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 years 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.