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MOUNTAINSIDE WESTCHESTER LLC
NPI 1457015331
Community/Behavioral Health in New York, NY

Active since October 26, 2021CLIA 33D2286998 · Waiver
243 W 18TH ST, NEW YORK, NY 10011(860) 362-5232(877) 861-6507 Get Directions Write a Review

NPPES record last updated: March 25, 2022. Verified against the NPPES registry weekly; last sync: September 13, 2026.

About Mountainside Westchester Llc NPPES

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

MOUNTAINSIDE WESTCHESTER LLC (NPI 1457015331), doing business as Mountainside - Chelsea, is a healthcare organization registered as a community/behavioral health in New York, New York and active in the NPI registry since October 2021. The organization holds a CLIA Waiver certificate valid through March 26, 2027 and lists Michelle Williamson, Director, as its authorized official.

NPPES Registry Identity

NPI1457015331
Entity TypeOrganization
Primary Taxonomy251S00000X
Legal Business NameMOUNTAINSIDE WESTCHESTER LLC
Location Address243 W 18TH STNew York, NY 10011-4569
Mailing AddressPo Box 717Canaan, CT 06018-0717 · (860) 362-5232 · Fax (877) 861-6507
Phone(860) 362-5232
Fax(877) 861-6507
Organization SubpartNo
Authorized OfficialMichelle WilliamsonDirector · (860) 362-5232
Enumeration DateOctober 26, 2021
Last NPPES UpdateMarch 25, 2022
NPPES CertifiedMarch 25, 2022
✔ NPI 1457015331 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyCommunity/Behavioral HealthAgencies
Taxonomy Code251S00000X
Definition
A private or public agency usually under local government jurisdiction, responsible for assuring the delivery of community based mental health, intellectual disabilities, substance abuse and/or behavioral health services to individuals with those disabilities. Services may range from companion care, respite, transportation, community integration, crisis intervention and stabilization, supported employment, day support, prevocational services, residential support, therapeutic and supportive consultation, environmental modifications, intensive in-home therapy and day treatment, in addition to traditional mental health and behavioral treatment.
Also ListedCase ManagementTaxonomy 251B00000X
243 W 18TH ST, New York, NY 10011
Open in Google Maps ↗

Other Names 1

Doing Business AsMountainside - Chelsea

CLIA Laboratory Certificates CMS CLIA

Laboratory certificates issued under the Clinical Laboratory Improvement Amendments (CLIA) program, which sets federal quality standards for human laboratory testing in the United States. There is no official CMS crosswalk between CLIA and NPI numbers; these certificates are associated with this NPI by matching facility names, locations and phone numbers in the CMS CLIA registry.

Certificate of Waiver 33D2286998

Artemis Partners LLC Dba Mountainside Chelsea · New York, NY
Active · expires Mar 26, 2027
CLIA Number33D2286998
Laboratory TypeComp. Outpatient Rehab Facility
Certificate Effective DateAugust 8, 2023
Certificate Expiration DateMarch 26, 2027
Laboratory DirectorAlison B. Altschuller
Laboratory Phone(860) 824-1397
Laboratory LocationArtemis Partners LLC Dba Mountainside Chelsea243 W 18th St, New York, NY 10011
CLIA data matches this NPI record on: Address Name
This certificate is issued to a laboratory to perform only waived tests.

Other Providers at the Same Location NPPES 4

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

TESSA L CANDIOTTI
Social Worker (Clinical)
243 W 18TH ST
NEW YORK, NY 10011
New York County (646) 965-8080
NICOLE BARMAN
Counselor (Mental Health)
243 W 18TH ST
NEW YORK, NY 10011
New York County (813) 767-0500
MOUNTAINSIDE - NYC LLC
Substance Abuse Rehabilitation Facility
243 W 18TH ST
NEW YORK, NY 10011
New York County (860) 362-5232
WYATT OFFIT
Social Worker
243 W 18TH ST
NEW YORK, NY 10011
New York County (212) 492-8088

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 Mountainside Westchester LLC's NPI number?

The NPI number for Mountainside Westchester LLC is 1457015331. It was assigned to this organization in the NPPES registry on October 26, 2021. The provider is doing business as Mountainside - Chelsea.

Where is Mountainside Westchester LLC located?

Mountainside Westchester LLC is located at 243 W 18th St, New York, NY 10011. The listed phone number is (860) 362-5232.

What is Mountainside Westchester LLC's specialty?

The primary specialty registered for this NPI is Community/Behavioral Health with taxonomy code 251S00000X.

Does Mountainside Westchester LLC hold a CLIA laboratory certificate?

Yes. A Certificate of Waiver (number 33D2286998) is associated with this NPI, valid through March 26, 2027. CLIA certificates authorize laboratory testing under the federal Clinical Laboratory Improvement Amendments program.

When was this NPI record last updated?

The NPPES record for Mountainside Westchester LLC was last updated on March 25, 2022. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 years 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.