IndividualActive
Marissa Fielstein, LMSW
NPI 1619383668 · Social Worker · Northport, NY
Marissa Fielstein, LMSW is a Social Worker provider in Northport, NY (NPI 1619383668).
Provider details
- NPI number
- 1619383668
- Entity type
- Individual
- Primary specialty
- Social WorkerBehavioral Health & Social Service Providers
- Credential
- LMSW
- Sex
- Female
- Sole proprietor
- Yes
- License
- 092019 (NY)
Specialties & taxonomies
Behavioral Health & Social Service Providers
Profile Score
Detailed profile(75/100 index)
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
11 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
79 Middleville Rd
Northport, NY 11768-2200
Phone: (631) 261-4400
Approximate (ZIP-level) locationGet directions
Mailing address
2 Hobart St
East Islip, NY 11730-2806
Registry dates
- Enumerated
- 2014-07-09
- Last updated
- 2014-07-09
Frequently asked questions
- What is Marissa Fielstein's NPI number?
- Marissa Fielstein's National Provider Identifier (NPI) is 1619383668, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Marissa Fielstein's specialty?
- Marissa Fielstein is listed in the NPPES registry with a primary specialty of Social Worker (Behavioral Health & Social Service Providers).
- Where is Marissa Fielstein located?
- Marissa Fielstein's practice location on file with NPPES is 79 Middleville Rd, Northport, NY 11768-2200.
- What is Marissa Fielstein's phone number?
- The practice phone number listed in the NPPES registry for Marissa Fielstein is (631) 261-4400.
- Is Marissa Fielstein's NPI active?
- Yes — Marissa Fielstein's NPI (1619383668) is active in the NPPES registry as of the last update on 2014-07-09.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.