STUART M GREENSTEIN MD
NPI 1942382114
Surgery in Valhalla, NY
About Stuart M Greenstein Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
STUART M GREENSTEIN MD (NPI 1942382114) is an individual surgery provider in Valhalla, New York, licensed in New York (162733) and active in the NPI registry since October 2006. He is enrolled in Medicare PECOS, is affiliated with Westchester Medical Center, and is a graduate of Harvard Medical School (1979).
NPPES Registry Identity
Specialties & Licenses
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare and accepts Medicare assignment
Stuart M Greenstein Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.
Medicare Billing Reassignments
2Medicare enrollment records show Stuart Greenstein reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Valhalla, NY 10595
- Reassigned Medicare billing, New York enrollment
- 1,663 clinicians in this Medicare group
Bronx, NY 10467
- Reassigned Medicare billing, New York enrollment
- 5,251 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Hospital Affiliations CMS Care Compare
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Westchester Medical Center
Acute Care Hospitals · Valhalla, NYPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 10595 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Medicare Quality Performance CMS QPP · MIPS
Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.
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.
VALHALLA, NY 10595
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 Stuart Greenstein's NPI number?
The NPI number for Stuart Greenstein is 1942382114. It was assigned to this individual provider in the NPPES registry on October 19, 2006.
Where is Stuart Greenstein located?
Stuart Greenstein practices at 100 Woods Rd Fl Acp3, Valhalla, NY 10595. The listed phone number is (914) 493-8916.
What is Stuart Greenstein's specialty?
The primary specialty registered for this NPI is Surgery with taxonomy code 208600000X.
Is Stuart Greenstein enrolled in Medicare?
Yes. Stuart Greenstein is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.
Which organizations bill Medicare for Stuart Greenstein's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Stuart Greenstein reassigns Medicare benefits to 2 organizations: Westchester Medical Center Advanced Physician Services PC (Valhalla, NY) and Montefiore Medical Center (Bronx, NY). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Stuart Greenstein's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
Is Stuart Greenstein affiliated with any hospitals?
According to CMS data, Stuart Greenstein is affiliated with Westchester Medical Center.
When was this NPI record last updated?
The NPPES record for Stuart Greenstein was last updated on May 31, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.
# Stuart M Greenstein, MD · NPI 1942382114
Surgery physician in Valhalla, New York. Individual provider, active in the CMS NPPES registry since October 19, 2006.
## Identity
- **NPI:** 1942382114 (Entity type: Individual)
- **Enumerated:** October 19, 2006
- **Primary specialty:** Surgery · taxonomy 208600000X
- **State license:** 162733 (New York)
- **Sole proprietor:** No
## Practice location
- **Address:** 100 WOODS RD FL ACP3, Valhalla, NY 10595-1530
- **Phone:** (914) 493-8916 · **Fax:** (914) 493-7595
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 2 organizations under Medicare reassignment (form CMS-855R): Westchester Medical Center Advanced Physician Services PC (NPI 1740687458, Valhalla, NY); Montefiore Medical Center (NPI 1063525152, Bronx, NY) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Harvard Medical School, class of 1979
## Record status
- **NPPES last updated:** May 31, 2023
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Source: [NPI Profile](https://npiprofile.com/npi/1942382114) · Data from the CMS NPPES public registry.