Grant Clarke, LCSW
NPI 1689812265 · Clinical Social Worker · Fullerton, CA
Enrolled with Medicare as Practitioner - Clinical Social Worker · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Grant Clarke, LCSW is a Clinical Social Worker provider in Fullerton, CA (NPI 1689812265).
Provider details
- NPI number
- 1689812265
- Entity type
- Individual
- Primary specialty
- Clinical Social WorkerBehavioral Health & Social Service Providers
- Credential
- LCSW
- Sex
- Male
- Sole proprietor
- No
- License
- LCS24617 (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
17 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
- 2009-02-04
- Last updated
- 2020-07-28
- Certified
- 2020-07-28
Frequently asked questions
- What is Grant Clarke's NPI number?
- Grant Clarke's National Provider Identifier (NPI) is 1689812265, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Grant Clarke's specialty?
- Grant Clarke is listed in the NPPES registry with a primary specialty of Clinical Social Worker (Behavioral Health & Social Service Providers).
- Where is Grant Clarke located?
- Grant Clarke's practice location on file with NPPES is 140 E Commonwealth Ave Ste 101, Fullerton, CA 92832-1905.
- What is Grant Clarke's phone number?
- The practice phone number listed in the NPPES registry for Grant Clarke is (714) 773-4111.
- Does Grant Clarke accept Medicare?
- Grant Clarke is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Grant Clarke's NPI active?
- Yes — Grant Clarke's NPI (1689812265) is active in the NPPES registry as of the last update on 2020-07-28.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.