Gwendolyn Williamson, LMSW
NPI 1639311202 · Clinical Social Worker · Portage, MI
Enrolled with Medicare as Practitioner - Clinical Social Worker · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Gwendolyn Williamson, LMSW is a Clinical Social Worker provider in Portage, MI (NPI 1639311202).
Provider details
- NPI number
- 1639311202
- Entity type
- Individual
- Primary specialty
- Clinical Social WorkerBehavioral Health & Social Service Providers
- Credential
- LMSW
- Sex
- Female
- Sole proprietor
- Yes
- License
- 6801079449 (MI)
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
2 documented practice locations
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
Additional practice locations (1)
- 4337 E Grand River Ave#147Howell, MI 48843-6583Phone: (248) 379-6975Fax: (248) 319-1143
Registry dates
- Enumerated
- 2009-03-29
- Last updated
- 2020-05-29
- Certified
- 2020-05-29
Frequently asked questions
- What is Gwendolyn Williamson's NPI number?
- Gwendolyn Williamson's National Provider Identifier (NPI) is 1639311202, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Gwendolyn Williamson's specialty?
- Gwendolyn Williamson is listed in the NPPES registry with a primary specialty of Clinical Social Worker (Behavioral Health & Social Service Providers).
- Where is Gwendolyn Williamson located?
- Gwendolyn Williamson's practice location on file with NPPES is 1125 E Milham Ave Ste B, Portage, MI 49002-3096.
- What is Gwendolyn Williamson's phone number?
- The practice phone number listed in the NPPES registry for Gwendolyn Williamson is (269) 312-1446.
- Does Gwendolyn Williamson accept Medicare?
- Gwendolyn Williamson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Gwendolyn Williamson's NPI active?
- Yes — Gwendolyn Williamson's NPI (1639311202) is active in the NPPES registry as of the last update on 2020-05-29.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.