Johna Hammaker
NPI 1821628256 · Addiction (Substance Use Disorder) Counselor · Fullerton, CA
Johna Hammaker is a Addiction (Substance Use Disorder) Counselor provider in Fullerton, CA (NPI 1821628256).
Provider details
- NPI number
- 1821628256
- Entity type
- Individual
- Primary specialty
- Addiction (Substance Use Disorder) CounselorBehavioral Health & Social Service Providers
- Sex
- Female
- Sole proprietor
- Yes
- License
- CI40501023 (CA)
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
6 yrs in NPPES registry
- Profile completeness38% of score
100% 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
- 2020-01-24
- Last updated
- 2023-10-23
- Certified
- 2023-10-23
Frequently asked questions
- What is Johna Hammaker's NPI number?
- Johna Hammaker's National Provider Identifier (NPI) is 1821628256, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Johna Hammaker's specialty?
- Johna Hammaker is listed in the NPPES registry with a primary specialty of Addiction (Substance Use Disorder) Counselor (Behavioral Health & Social Service Providers).
- Where is Johna Hammaker located?
- Johna Hammaker's practice location on file with NPPES is 771 W Orangethorpe Ave, Fullerton, CA 92832-2806.
- What is Johna Hammaker's phone number?
- The practice phone number listed in the NPPES registry for Johna Hammaker is (714) 879-0929.
- Is Johna Hammaker's NPI active?
- Yes — Johna Hammaker's NPI (1821628256) is active in the NPPES registry as of the last update on 2023-10-23.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.