Garry Williamson
NPI 1194911818 · Addiction (Substance Use Disorder) Counselor · Oakland, CA
Garry Williamson is a Addiction (Substance Use Disorder) Counselor provider in Oakland, CA (NPI 1194911818).
Provider details
- NPI number
- 1194911818
- Entity type
- Individual
- Primary specialty
- Addiction (Substance Use Disorder) CounselorBehavioral Health & Social Service Providers
- Sex
- Female
- Sole proprietor
- No
Specialties & taxonomies
Behavioral Health & Social Service Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
18 yrs in NPPES registry
- Profile completeness38% of score
83% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-09-16
- Last updated
- 2021-05-14
- Certified
- 2021-04-20
Frequently asked questions
- What is Garry Williamson's NPI number?
- Garry Williamson's National Provider Identifier (NPI) is 1194911818, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Garry Williamson's specialty?
- Garry Williamson is listed in the NPPES registry with a primary specialty of Addiction (Substance Use Disorder) Counselor (Behavioral Health & Social Service Providers).
- Where is Garry Williamson located?
- Garry Williamson's practice location on file with NPPES is 1124 International Blvd, Oakland, CA 94606-4331.
- What is Garry Williamson's phone number?
- The practice phone number listed in the NPPES registry for Garry Williamson is (510) 533-0800.
- Is Garry Williamson's NPI active?
- Yes — Garry Williamson's NPI (1194911818) is active in the NPPES registry as of the last update on 2021-05-14.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.