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Stephen Mast, L.M.S.W.
NPI 1558671735 · Social Worker · West Sayville, NY
Stephen Mast, L.M.S.W. is a Social Worker provider in West Sayville, NY (NPI 1558671735).
Provider details
- NPI number
- 1558671735
- Entity type
- Individual
- Primary specialty
- Social WorkerBehavioral Health & Social Service Providers
- Credential
- L.M.S.W.
- Sex
- Male
- Sole proprietor
- No
- License
- 081999-1 (NY)
Specialties & taxonomies
Behavioral Health & Social Service Providers
Profile Score
Detailed profile(82/100 index)
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
15 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
93 Main St
Suite 1j
West Sayville, NY 11796
Phone: (631) 502-5220
Fax: (631) 256-9353
Approximate (ZIP-level) locationGet directions
Mailing address
9525 Queens Blvd Ste 812
Rego Park, NY 11374-4522
Registry dates
- Enumerated
- 2010-10-20
- Last updated
- 2025-09-16
- Certified
- 2025-09-16
Frequently asked questions
- What is Stephen Mast's NPI number?
- Stephen Mast's National Provider Identifier (NPI) is 1558671735, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Stephen Mast's specialty?
- Stephen Mast is listed in the NPPES registry with a primary specialty of Social Worker (Behavioral Health & Social Service Providers).
- Where is Stephen Mast located?
- Stephen Mast's practice location on file with NPPES is 93 Main St, West Sayville, NY 11796.
- What is Stephen Mast's phone number?
- The practice phone number listed in the NPPES registry for Stephen Mast is (631) 502-5220.
- Is Stephen Mast's NPI active?
- Yes — Stephen Mast's NPI (1558671735) is active in the NPPES registry as of the last update on 2025-09-16.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.