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RALPH BAILEY HANAHAN M.D.
NPI 1801986641
Radiology - Therapeutic Radiology in Santa Rosa, CA

Active since October 13, 2006
3555 ROUND BARN CIR, SANTA ROSA, CA 95403(707) 522-6875(707) 576-0445 Get Directions Write a Review

NPPES record last updated: September 11, 2025. Verified against the NPPES registry weekly; last sync: August 09, 2026.

About Ralph Bailey Hanahan M.d. NPPES

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

RALPH BAILEY HANAHAN M.D. (NPI 1801986641) is an individual therapeutic radiology provider in Santa Rosa, California, licensed in California (C30500) and active in the NPI registry since October 2006.

NPPES Registry Identity

NPI1801986641
Entity TypeIndividualMale
Primary Taxonomy2085R0203X
Provider Legal NameRALPH BAILEY HANAHANCredential: M.D.
Location Address3555 ROUND BARN CIRSanta Rosa, CA 95403-1757
Mailing Address3555 Round Barn CirSanta Rosa, CA 95403-1757 · (707) 522-6875 · Fax (707) 576-0445
Phone(707) 522-6875
Fax(707) 576-0445
Sole ProprietorNo
Enumeration DateOctober 13, 2006
Last NPPES UpdateSeptember 11, 2025
✔ NPI 1801986641 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyRadiology · Therapeutic RadiologyAllopathic & Osteopathic Physicians
Taxonomy Code2085R0203X
License✔ Licensed in CA · C30500
Definition
Therapeutic Radiology certificate name was changed to Radiation Oncology. Use Radiation Oncology.
Also ListedRadiology · Radiation OncologyTaxonomy 2085R0001X · License C30500 (CA)

Other Identifiers 1

Medicaid00C305000CA

Other Providers at the Same Location NPPES 17

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

JARROD PAUL HOLMES MD
Internal Medicine (Hematology & Oncology)
3555 ROUND BARN CIR
SANTA ROSA, CA 95403
Sonoma County (707) 528-1050
ST JUDE HOSPITAL YORBA LINDA
Internal Medicine (Medical Oncology)
3555 ROUND BARN CIR
SANTA ROSA, CA 95403
Sonoma County (707) 528-1050
MR. JOSEPH C. SMIHULA NP
Nurse Practitioner (Adult Health)
3555 ROUND BARN CIR
SANTA ROSA, CA 95403
Sonoma County (707) 528-1050
YAO YAO GUAN POLLOCK MD
Internal Medicine (Hematology & Oncology)
3555 ROUND BARN CIR
SANTA ROSA, CA 95403
Sonoma County (707) 528-1050
LEENA AGRAWAL PHARMD
Pharmacist (Oncology)
3555 ROUND BARN CIR
SANTA ROSA, CA 95403
Sonoma County (707) 521-3891
REDWOOD REGIONAL MEDICAL GROUP INC
Internal Medicine (Hematology & Oncology)
3555 ROUND BARN CIR
SANTA ROSA, CA 95403
Sonoma County (707) 525-6124
WES SHEN-LIN LEE M.D.
Internal Medicine (Medical Oncology)
3555 ROUND BARN CIR
SANTA ROSA, CA 95403
Sonoma County (707) 528-1050
ST JUDE HOSPITAL YORBA LINDA
Internal Medicine (Medical Oncology)
3555 ROUND BARN CIR
SANTA ROSA, CA 95403
Sonoma County (707) 528-1050

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 Ralph Hanahan's NPI number?

The NPI number for Ralph Hanahan is 1801986641. It was assigned to this individual provider in the NPPES registry on October 13, 2006.

Where is Ralph Hanahan located?

Ralph Hanahan practices at 3555 Round Barn Cir, Santa Rosa, CA 95403. The listed phone number is (707) 522-6875.

What is Ralph Hanahan's specialty?

The primary specialty registered for this NPI is Radiology, specializing in Therapeutic Radiology, with taxonomy code 2085R0203X.

When was this NPI record last updated?

The NPPES record for Ralph Hanahan was last updated on September 11, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 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.