STEPHEN F MAST L.M.S.W.
NPI 1558671735
Social Worker in West Sayville, NY

Q: What is Stephen Mast's NPI number?

The NPI number for Stephen Mast is 1558671735. It was assigned to this individual provider in the NPPES registry on October 20, 2010.

Q: What is Stephen Mast's specialty?

The primary specialty registered for this NPI is Social Worker with taxonomy code 104100000X.

Q: When was this NPI record last updated?

The NPPES record for Stephen Mast was last updated on September 16, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since October 20, 2010

93 MAIN ST, SUITE 1J, WEST SAYVILLE, NY 11796(631) 502-5220(631) 256-9353 Get Directions Write a Review

NPPES record last updated: September 16, 2025. Verified against the NPPES registry weekly; last sync: September 06, 2026.

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About Stephen F Mast L.m.s.w. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

STEPHEN F MAST L.M.S.W. (NPI 1558671735) is an individual social worker in West Sayville, New York, licensed in New York (081999-1) and active in the NPI registry since October 2010.

NPPES Registry Identity

NPI1558671735

Entity TypeIndividualMale

Primary Taxonomy104100000X

Provider Legal NameSTEPHEN F MASTCredential: L.M.S.W.

Location Address93 MAIN ST, SUITE 1JWest Sayville, NY 11796

Mailing Address9525 Queens Blvd Ste 812Rego Park, NY 11374-4522 · (718) 896-6500 · Fax (347) 868-6427

Phone(631) 502-5220

Fax(631) 256-9353

Sole ProprietorNo

Enumeration DateOctober 20, 2010

Last NPPES UpdateSeptember 16, 2025

NPPES CertifiedSeptember 16, 2025

✔ NPI 1558671735 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtySocial WorkerBehavioral Health & Social Service Providers

Taxonomy Code104100000X

License✔ Licensed in NY · 081999-1

Definition

A social worker is a person who is qualified by a Social Work degree, and licensed, certified or registered by the state as a social worker to practice within the scope of that license. A social worker provides assistance and counseling to clients and their families who are dealing with social, emotional and environmental problems. Social work services may be rendered to individuals, families, groups, and the public.

93 MAIN ST, West Sayville, NY 11796

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Other Providers at the Same Location NPPES 11

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

MIND BODY MENTAL HEALTH COUNSELING PPLC

Counselor (Mental Health)

93 MAIN ST
WEST SAYVILLE, NY 11796

Suffolk County (631) 312-4175

JULIANNA AMBROSIO

Counselor (Mental Health)

93 MAIN ST
WEST SAYVILLE, NY 11796

Suffolk County (631) 517-3251

JAMES MAMMONE LMSW

Social Worker (Clinical)

93 MAIN ST
WEST SAYVILLE, NY 11796

Suffolk County (631) 474-1533

MR. DAVID ANTHONY TORRES

Counselor (Mental Health)

93 MAIN ST
WEST SAYVILLE, NY 11796

Suffolk County (631) 474-1533

GINA MARIE ZORN LMSW

Social Worker

93 MAIN ST
WEST SAYVILLE, NY 11796

Suffolk County (631) 769-4606

GREGORY COUBA

Counselor (Mental Health)

93 MAIN ST
WEST SAYVILLE, NY 11796

Suffolk County (631) 502-5220

INNOVATIONS COUNSELING, LCSW PLLC

Social Worker (Clinical)

93 MAIN ST, SUITE 1J
WEST SAYVILLE, NY 11796

Suffolk County (631) 747-6652

DR. SALVATORE BELLAFIORE ED.D, MS, BS

Counselor (Mental Health)

93 MAIN ST
WEST SAYVILLE, NY 11796

Suffolk County (631) 987-0352

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Stephen Mast's NPI number?

The NPI number for Stephen Mast is 1558671735. It was assigned to this individual provider in the NPPES registry on October 20, 2010.

Where is Stephen Mast located?

Stephen Mast practices at 93 Main St Suite 1J, West Sayville, NY 11796. The listed phone number is (631) 502-5220.

What is Stephen Mast's specialty?

The primary specialty registered for this NPI is Social Worker with taxonomy code 104100000X.

When was this NPI record last updated?

The NPPES record for Stephen Mast was last updated on September 16, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.