Jeff Westermann

Jeff Westermann is a Addiction (Substance Use Disorder) Counselor provider (Counselor) practicing in Fairfield, CA, registered in the NPPES registry with NPI 1598267197 since 2018. Practices at Archway Recovery Services Inc (listed at the same practice address in NPPES).

✓ Active NPI ✓ Valid NPI checksum

NPI	1598267197
Entity type	Individual (Type 1)
Name	Jeff Westermann
Sex	Male
Practice address	609 JEFFERSON ST, Fairfield, CA, 94533
Phone	7073999190
Enumeration date	2018-02-28
Last updated in NPPES	2026-05-05

Taxonomy & licenses

Taxonomy code	Specialty	Primary	License	State
101YA0400X	Addiction (Substance Use Disorder) Counselor	Primary	24372	CA

Copy-ready billing details

Provider: Jeff Westermann
NPI: 1598267197
Taxonomy: 101YA0400X (Addiction (Substance Use Disorder) Counselor)
Address: 609 JEFFERSON ST, Fairfield, CA, 94533

Other providers at this practice address

NPI	Name	Type	Specialty	Location
1407908221	Sharon Bender	Individual	Clinical Social Worker	Fairfield, CA
1447928833	Waverly Cook	Individual	Addiction (Substance Use Disorder) Counselor	Fairfield, CA
1982376174	Amanda Mitchell	Individual	Addiction (Substance Use Disorder) Counselor	Fairfield, CA
1689321556	Archway Recovery Services Inc	Organization	Substance Abuse Rehabilitation Facility	Fairfield, CA
1548918832	Kathryn Wagoner	Individual	Addiction (Substance Use Disorder) Counselor	Fairfield, CA

Verify this record

Cross-check NPI 1598267197 against the authoritative CMS record: view Jeff Westermann on the official NPPES registry .

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes — even if the provider moves or changes specialty. Read the full guide or validate an NPI number.

Frequently asked questions

Is this the official NPI registry?

No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

What specialty is Jeff Westermann?

Jeff Westermann is registered in NPPES with the primary taxonomy of Addiction (Substance Use Disorder) Counselor. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2026-05-05.