DR. GERALDINE C. DIAZ D.O.
NPI 1003987967
Anesthesiology in Brentwood, NY
About Dr. Geraldine C. Diaz D.o. NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. GERALDINE C. DIAZ D.O. (NPI 1003987967) is an individual anesthesiology provider in Brentwood, New York, licensed in New York (225683) and active in the NPI registry since November 2006. She is enrolled in Medicare PECOS, maintains 4 additional practice locations, and is a graduate of Philadelphia College Of Osteopathic Medicine (2001).
NPPES Registry Identity
Specialties & Licenses 2
Secondary Practice Locations 4
Other Identifiers 1
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
Dr. Geraldine C. Diaz D.o. 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
5Medicare enrollment records show Geraldine Diaz reassigns Medicare billing to 5 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Melville, NY 11747
- Reassigned Medicare billing, New York enrollment
- 508 clinicians in this Medicare group
Roslyn, NY 11576
- Reassigned Medicare billing, New York enrollment
- 162 clinicians in this Medicare group
Valley Stream, NY 11581
- Reassigned Medicare billing, New York enrollment
- 305 clinicians in this Medicare group
Bronx, NY 10467
- Reassigned Medicare billing, New York enrollment
- 5,251 clinicians in this Medicare group
New York, NY 10021
- Reassigned Medicare billing, New York enrollment
- 78 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.
Areas of Expertise CMS Part B claims 5
Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.
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.
BRENTWOOD, NY 11717
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 Geraldine Diaz's NPI number?
The NPI number for Geraldine Diaz is 1003987967. It was assigned to this individual provider in the NPPES registry on November 13, 2006.
Where is Geraldine Diaz located?
Geraldine Diaz practices at 601 Suffolk Ave, Brentwood, NY 11717. The listed phone number is (631) 231-4455.
What is Geraldine Diaz's specialty?
The primary specialty registered for this NPI is Anesthesiology with taxonomy code 207L00000X.
Is Geraldine Diaz enrolled in Medicare?
Yes. Geraldine Diaz 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 Geraldine Diaz's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Geraldine Diaz reassigns Medicare benefits to 5 organizations: North American Partners In Anesthesia LLP (Melville, NY), New York Cardiovascular Anesthesiologists, P.C. (Roslyn, NY), Sedation Vacation Perioperative Medicine PLLC (Valley Stream, NY), Montefiore Medical Center (Bronx, NY) and R & n Anesthesia PLLC (New York, 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 Geraldine Diaz'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 Geraldine Diaz was last updated on January 30, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 9 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.
# Dr. Geraldine C. Diaz, D.O. · NPI 1003987967
Anesthesiology physician in Brentwood, New York. Individual provider, active in the CMS NPPES registry since November 13, 2006.
## Identity
- **NPI:** 1003987967 (Entity type: Individual)
- **Enumerated:** November 13, 2006
- **Primary specialty:** Anesthesiology · taxonomy 207L00000X
- **State license:** 225683 (New York)
- **Sole proprietor:** No
## Practice location
- **Address:** 601 SUFFOLK AVE, Brentwood, NY 11717-4309
- **Phone:** (631) 231-4455
## 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:** 5 organizations under Medicare reassignment (form CMS-855R): North American Partners In Anesthesia LLP (NPI 1649264706, Melville, NY); New York Cardiovascular Anesthesiologists, P.C. (NPI 1801834411, Roslyn, NY); Sedation Vacation Perioperative Medicine PLLC (NPI 1891235404, Valley Stream, NY); Montefiore Medical Center (NPI 1063525152, Bronx, NY); R & n Anesthesia PLLC (NPI 1447657275, New York, NY) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Philadelphia College Of Osteopathic Medicine, class of 2001
## Record status
- **NPPES last updated:** January 30, 2026
- **Other identifiers:** Other Z120519 (AZ)
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Source: [NPI Profile](https://npiprofile.com/npi/1003987967) · Data from the CMS NPPES public registry.