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Dr. William Joseph Sullivan, DNP, FNP

Family Nurse Practitioner in Leeds, MA · enumerated 2011.

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

National Provider Identifier

1184991150

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Registry record

Entity type Individual (Type 1)
Name Dr. William Joseph Sullivan
Credential DNP, FNP
Sex Male
Practice address 421 N Main St, Leeds, MA, 01053
Phone (413) 627-2625
Enumeration date Nov 19, 2011
Last updated in NPPES Nov 19, 2011

Taxonomy & licenses

363LF0000X Family Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 215708 (MA) Primary
DNP · Doctor of Nursing Practice: A clinical doctorate for advanced practice nurses. About the DNP credential

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.

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Frequently asked questions

What is the NPI number for William Sullivan?
The National Provider Identifier (NPI) for William Sullivan is 1184991150, a Type 1 (individual) record in the CMS NPPES registry.
Where does William Sullivan practice?
The practice location on file with NPPES is in Leeds, MA. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-11-19.