NPI Portal NPI Lookup & Verification

Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Mr. Dennis K Duffy, P.A.

Physician Assistant in Stony Brook, NY · enumerated 2006.

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

National Provider Identifier

1932136447

Verified

See something wrong? Report a correction

Registry record

Entity type Individual (Type 1)
Name Mr. Dennis K Duffy
Credential P.A.
Sex Male
Practice address New York Spine and Brain Surgery, Hsc T12 Rm 080, Stony Brook, NY, 11794
Phone (631) 444-1116
Fax (631) 444-1535
Enumeration date Jun 28, 2006
Last updated in NPPES Jun 11, 2014

Taxonomy & licenses

363A00000X Physician Assistant Physician Assistants & Advanced Practice Nursing Providers · License 004529 (NY) Primary
PA · Physician Assistant: A licensed clinician who practices medicine in collaboration with physicians, trained in a graduate PA program. About the PA credential

Other identifiers

Identifier Type State Issuer
02599604 Medicaid NY -

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

Where does Dennis Duffy practice?
The practice location on file with NPPES is in Stony Brook, NY. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Dennis Duffy?
The National Provider Identifier (NPI) for Dennis Duffy is 1932136447, a Type 1 (individual) record in the CMS NPPES registry.

Other providers at this practice address

Browse all →

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2014-06-11.