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Dr. William Arthur Monaco, O.D., PH.D.

Optometrist in Newark, DE · enumerated 2006.

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

National Provider Identifier

1427091057

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Registry record

Entity type Individual (Type 1)
Name Dr. William Arthur Monaco
Credential O.D., PH.D.
Sex Male
Practice address 23 Lynam Lookout Dr, Newark, DE, 19702
Fax (302) 292-2209
Enumeration date Jun 13, 2006
Last updated in NPPES Oct 20, 2011

Taxonomy & licenses

152W00000X Optometrist Eye and Vision Services Providers · License I3-0001253 (DE) Primary
OD · Doctor of Optometry: A licensed optometrist providing primary vision care, eye exams, and corrective lenses. About the OD credential

Other identifiers

Identifier Type State Issuer
P00029433 Other DE RAILROAD MEDICARE
1000023163 Medicaid DE -

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

Where does William Monaco practice?
The practice location on file with NPPES is in Newark, DE. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for William Monaco?
The National Provider Identifier (NPI) for William Monaco is 1427091057, a Type 1 (individual) record in the CMS NPPES registry.

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-10-20.