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MR. SEAN P DONNELLY PEER SUPPORT SPECIAL
NPI 1255229530
Counselor - Addiction (Substance Use Disorder) in San Mateo, CA

Active since June 25, 2025
416 2ND AVE, SAN MATEO, CA 94401(650) 579-7881 Get Directions Write a Review

NPPES record last updated: June 17, 2026. Verified against the NPPES registry weekly; last sync: July 19, 2026.

About Mr. Sean P Donnelly Peer Support Special NPPES

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

MR. SEAN P DONNELLY PEER SUPPORT SPECIAL (NPI 1255229530) is an individual addiction (substance use disorder) provider in San Mateo, California, licensed in California (SUDRCI25906) and active in the NPI registry since June 2025.

NPPES Registry Identity

NPI1255229530
Entity TypeIndividualMale
Primary Taxonomy101YA0400X
Provider Legal NameMR. SEAN P DONNELLYCredential: PEER SUPPORT SPECIAL
Location Address416 2ND AVESan Mateo, CA 94401-3205
Mailing Address114 S Delaware StSan Mateo, CA 94401-3222 · (650) 579-7881
Phone(650) 579-7881
Sole ProprietorNo
Enumeration DateJune 25, 2025
Last NPPES UpdateJune 17, 2026
NPPES CertifiedJune 17, 2026
✔ NPI 1255229530 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyCounselor · Addiction (Substance Use Disorder)Behavioral Health & Social Service Providers
Taxonomy Code101YA0400X
License✔ Licensed in CA · SUDRCI25906
Also ListedPeer SpecialistTaxonomy 175T00000X · License MPSS-MKGVZO (CA)
416 2ND AVE, San Mateo, CA 94401
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Other Providers at the Same Location NPPES 5

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

GARY JAMES SMITH CADC II, ICADC
Counselor (Addiction (Substance Use Disorder))
416 2ND AVE
SAN MATEO, CA 94401
San Mateo County (650) 579-7158
JASON DAVID SANDERS
Counselor (Addiction (Substance Use Disorder))
416 2ND AVE
SAN MATEO, CA 94401
San Mateo County (650) 579-7158
MR. WILLIAM HOLMAN
Counselor (Addiction (Substance Use Disorder))
416 2ND AVE
SAN MATEO, CA 94401
San Mateo County (650) 579-7881
CAMINAR
Clinic/Center
416 2ND AVE
SAN MATEO, CA 94401
San Mateo County (650) 333-4226
MRS. KIMBERLY RILEY
Counselor (Addiction (Substance Use Disorder))
416 2ND AVE
SAN MATEO, CA 94401
San Mateo County (650) 579-7881

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 Sean Donnelly's NPI number?

The NPI number for Sean Donnelly is 1255229530. It was assigned to this individual provider in the NPPES registry on June 25, 2025.

Where is Sean Donnelly located?

Sean Donnelly practices at 416 2nd Ave, San Mateo, CA 94401. The listed phone number is (650) 579-7881.

What is Sean Donnelly's specialty?

The primary specialty registered for this NPI is Counselor, specializing in Addiction (Substance Use Disorder), with taxonomy code 101YA0400X.

When was this NPI record last updated?

The NPPES record for Sean Donnelly was last updated on June 17, 2026. NPI Profile syncs with the weekly NPPES data releases published by CMS.