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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. Gerard Stanley Mason, O.D.

Optometrist in Glastonbury, CT · enumerated 2007.

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

National Provider Identifier

1598821621

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Registry record

Entity type Individual (Type 1)
Name Dr. Gerard Stanley Mason
Credential O.D.
Sex Male
Practice address Glastonbury, CT, 06033
Phone (860) 633-6236
Enumeration date Jan 1, 2007
Last updated in NPPES Jul 8, 2007

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

152W00000X Optometrist Eye and Vision Services Providers · License CT719 (CT) Primary
OD · Doctor of Optometry: A licensed optometrist providing primary vision care, eye exams, and corrective lenses. About the OD 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

Where does Gerard Mason practice?
The practice location on file with NPPES is in Glastonbury, CT. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Gerard Mason?
The National Provider Identifier (NPI) for Gerard Mason is 1598821621, a Type 1 (individual) record in the CMS NPPES registry.

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.