Margaret Koster, LCSW
NPI 1770609919 · Psychologist · Willits, CA
Margaret Koster, LCSW is a Psychologist provider in Willits, CA (NPI 1770609919).
Provider details
- NPI number
- 1770609919
- Entity type
- Individual
- Primary specialty
- PsychologistBehavioral Health & Social Service Providers
- Credential
- LCSW
- Sex
- Female
- Sole proprietor
- Yes
- License
- LCS5820 (CA)
Specialties & taxonomies
Behavioral Health & Social Service Providers
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
19 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
- 2007-03-21
- Last updated
- 2025-09-11
Frequently asked questions
- What is Margaret Koster's NPI number?
- Margaret Koster's National Provider Identifier (NPI) is 1770609919, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Margaret Koster's specialty?
- Margaret Koster is listed in the NPPES registry with a primary specialty of Psychologist (Behavioral Health & Social Service Providers).
- Where is Margaret Koster located?
- Margaret Koster's practice location on file with NPPES is 16100 N Highway 101 Spc 72, Willits, CA 95490-9715.
- What is Margaret Koster's phone number?
- The practice phone number listed in the NPPES registry for Margaret Koster is (707) 459-5970.
- Is Margaret Koster's NPI active?
- Yes — Margaret Koster's NPI (1770609919) is active in the NPPES registry as of the last update on 2025-09-11.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.