JOHN T. MATHER MEMORIAL HOSPITAL
NPI 1104913748
Emergency Medicine in Port Jefferson, NY
About John T. Mather Memorial Hospital NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
JOHN T. MATHER MEMORIAL HOSPITAL (NPI 1104913748) is a healthcare organization registered as an emergency medicine in Port Jefferson, New York and active in the NPI registry since October 2006. The organization lists Sharon Donnelly, Director, as its authorized official.
NPPES Registry Identity
Specialties & Licenses
Group Practice 1
Medicare Participation & PECOS CMS
Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
John T. Mather Memorial Hospital is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Clinicians Billing Medicare Through This Organization
232Medicare enrollment records show 232 clinicians reassign Medicare billing to John T. Mather Memorial Hospital, which bills Medicare for the services they deliver. Of these, 1 practice at this address and 106 within 10 miles. Listed here are the 20 practicing nearest to this location.
Clinicians by Medicare Specialty 14
Nearest to this location (20)
See all 232Port Jefferson, NY 11777
Port Jefferson, NY 11777
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
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 John T. Mather Memorial Hospital's NPI number?
The NPI number for John T. Mather Memorial Hospital is 1104913748. It was assigned to this organization in the NPPES registry on October 6, 2006.
Where is John T. Mather Memorial Hospital located?
John T. Mather Memorial Hospital is located at 75 N Country Rd, Port Jefferson, NY 11777. The listed phone number is (631) 473-1320.
What is John T. Mather Memorial Hospital's specialty?
The primary specialty registered for this NPI is Emergency Medicine with taxonomy code 207P00000X.
Is John T. Mather Memorial Hospital enrolled in Medicare?
Yes. John T. Mather Memorial Hospital is registered in the Medicare PECOS enrollment system.
How many clinicians bill Medicare through John T. Mather Memorial Hospital?
According to the CMS Revalidation Reassignment List (October 2026 release), 232 clinicians in 14 Medicare specialties reassign their Medicare billing to John T. Mather Memorial Hospital. A 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 the clinician's services. The largest specialties are Nurse Practitioner (70), Emergency Medicine (62) and Internal Medicine (29). Of these, 1 practice at this address and 106 within 10 miles. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
When was this NPI record last updated?
The NPPES record for John T. Mather Memorial Hospital was last updated on May 19, 2015. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 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.
# John T. Mather Memorial Hospital · NPI 1104913748
Emergency Medicine organization in Port Jefferson, New York. Organization record, active in the CMS NPPES registry since October 6, 2006.
## Identity
- **NPI:** 1104913748 (Entity type: Organization)
- **Enumerated:** October 6, 2006
- **Primary specialty:** Emergency Medicine · taxonomy 207P00000X
- **Organization subpart:** No
- **Authorized official:** Sharon Donnelly, DIRECTOR
## Practice location
- **Address:** 75 N COUNTRY RD, Port Jefferson, NY 11777-2119
- **Phone:** (631) 473-1320 · **Fax:** (631) 474-4667
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **Clinicians billing through this organization:** 232 clinicians in 14 Medicare specialties reassign Medicare billing to this organization (form CMS-855R); largest: Nurse Practitioner (70), Emergency Medicine (62), Internal Medicine (29); 1 practice at this address and 106 within 10 miles; [full list](https://npiprofile.com/npi/1104913748/clinicians) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** May 19, 2015
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Source: [NPI Profile](https://npiprofile.com/npi/1104913748) · Data from the CMS NPPES public registry.