MARGOT VALERIE MARRERO-STEIN RN-PNP
NPI 1861662975
Nurse Practitioner - Pediatrics in Valhalla, NY
About Margot Valerie Marrero-stein Rn-pnp NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MARGOT VALERIE MARRERO-STEIN RN-PNP (NPI 1861662975) is an individual pediatrics provider in Valhalla, New York, licensed in New York (F381930-1) and active in the NPI registry since March 2008. She is enrolled in Medicare PECOS.
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 (PECOS)
Margot Valerie Marrero-stein Rn-pnp is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignments
2Medicare enrollment records show Margot Marrero-stein 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
Hawthorne, NY 10532
- Reassigned Medicare billing, New York enrollment
- 511 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.
Physician 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.
Other Providers at the Same Location NPPES 20
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 Margot Marrero-stein's NPI number?
The NPI number for Margot Marrero-stein is 1861662975. It was assigned to this individual provider in the NPPES registry on March 4, 2008.
Where is Margot Marrero-stein located?
Margot Marrero-stein practices at 503 Grasslands Rd Suite 200, Valhalla, NY 10595. The listed phone number is (914) 304-5300.
What is Margot Marrero-stein's specialty?
The primary specialty registered for this NPI is Nurse Practitioner, specializing in Pediatrics, with taxonomy code 363LP0200X.
Is Margot Marrero-stein enrolled in Medicare?
Yes. Margot Marrero-stein is registered in the Medicare PECOS enrollment system.
Which organizations bill Medicare for Margot Marrero-stein's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Margot Marrero-stein reassigns Medicare benefits to 2 organizations: Westchester Medical Center Advanced Physician Services PC (Valhalla, NY) and Boston Children's Health Physicians, LLP (Hawthorne, 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 Margot Marrero-stein's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
When was this NPI record last updated?
The NPPES record for Margot Marrero-stein was last updated on March 4, 2008. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 18 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.
# Margot Valerie Marrero-Stein, RN-PNP · NPI 1861662975
Pediatrics physician in Valhalla, New York. Individual provider, active in the CMS NPPES registry since March 4, 2008.
## Identity
- **NPI:** 1861662975 (Entity type: Individual)
- **Enumerated:** March 4, 2008
- **Primary specialty:** Nurse Practitioner - Pediatrics · taxonomy 363LP0200X
- **State license:** F381930-1 (New York)
- **Sole proprietor:** No
## Practice location
- **Address:** 503 GRASSLANDS RD, SUITE 200, Valhalla, NY 10595-1503
- **Phone:** (914) 304-5300 · **Fax:** (914) 345-1753
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **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); Boston Children's Health Physicians, LLP (NPI 1467454967, Hawthorne, NY) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** March 4, 2008
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Source: [NPI Profile](https://npiprofile.com/npi/1861662975) · Data from the CMS NPPES public registry.