Type 2 · Organization ✓ Active NPI ✓ Valid NPI checksum

John T Mather Memorial Hospital

General Acute Care Hospital in Port Jefferson, NY · enumerated 2014 · authorized official Joseph Wisnoski, Vp Finance.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1881082691

Verified

See something wrong? Report a correction

Registry record

Entity type Organization (Type 2)

Legal business name John T Mather Memorial Hospital

Practice address 75 N Country Rd, Port Jefferson, NY, 11777

Phone (631) 473-1320

Fax (631) 473-1382

Enumeration date Dec 31, 2014

Last updated in NPPES Dec 31, 2014

Taxonomy & classification

282N00000X General Acute Care Hospital Hospitals · License 5149000 (NY) Primary

Authorized official

Name Joseph Wisnoski

Title Vp Finance

Phone (631) 473-1320

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

Read the full guide → Validate an NPI →

Frequently asked questions

What type of organization is John T Mather Memorial Hospital?

John T Mather Memorial Hospital is registered in NPPES as a General Acute Care Hospital (its primary provider taxonomy).

What is a Type 2 NPI?

A Type 2 NPI identifies an organization (group practice, hospital, pharmacy, lab), while Type 1 NPIs identify individual providers. Organizations bill under their Type 2 NPI.

Providers at this address

Browse all →

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2014-12-31.