NPI Portal NPI Lookup & Verification

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

Dr. Jack Grey Hall, O.D.

Optometrist in Modesto, CA · enumerated 2007.

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

National Provider Identifier

1639228331

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Registry record

Entity type Individual (Type 1)
Name Dr. Jack Grey Hall
Credential O.D.
Sex Male
Practice address Modesto, CA, 95356
Phone (209) 543-0220
Fax (209) 543-0220
Enumeration date Jan 10, 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 6455T (CA) 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

Is NPI 1639228331 active?
Yes, as of the latest NPPES snapshot, NPI 1639228331 is active (record last updated 2007-07-08).
How do I verify Jack Hall's NPI record?
Cross-check NPI 1639228331 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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