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Nathan Flessner, LCSW
NPI 1619688603 · Clinical Social Worker · Chicago, IL
Nathan Flessner, LCSW is a Clinical Social Worker provider in Chicago, IL (NPI 1619688603).
Provider details
- NPI number
- 1619688603
- Entity type
- Individual
- Primary specialty
- Clinical Social WorkerBehavioral Health & Social Service Providers
- Credential
- LCSW
- Sex
- Male
- Sole proprietor
- No
- License
- 149.025006 (IL)
Specialties & taxonomies
Behavioral Health & Social Service Providers
Profile Score
Established profile(59/100 index)
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
3 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
2755 N Pine Grove Ave
Chicago, IL 60614-6109
Phone: (312) 259-2665
Street-level locationGet directions
Mailing address
3138 W Lyndale St Unit 1
Chicago, IL 60647-2824
Registry dates
- Enumerated
- 2022-12-09
- Last updated
- 2022-12-09
- Certified
- 2022-12-09
Frequently asked questions
- What is Nathan Flessner's NPI number?
- Nathan Flessner's National Provider Identifier (NPI) is 1619688603, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Nathan Flessner's specialty?
- Nathan Flessner is listed in the NPPES registry with a primary specialty of Clinical Social Worker (Behavioral Health & Social Service Providers).
- Where is Nathan Flessner located?
- Nathan Flessner's practice location on file with NPPES is 2755 N Pine Grove Ave, Chicago, IL 60614-6109.
- What is Nathan Flessner's phone number?
- The practice phone number listed in the NPPES registry for Nathan Flessner is (312) 259-2665.
- Is Nathan Flessner's NPI active?
- Yes — Nathan Flessner's NPI (1619688603) is active in the NPPES registry as of the last update on 2022-12-09.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.