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Errol O Grannum

Ophthalmology Physician in Mcallen, TX · enumerated 2006 · authorized official Errol Grannum, Owner.

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

National Provider Identifier

1457377194

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Registry record

Entity type Organization (Type 2)
Legal business name Errol O Grannum
Practice address 1910 S 1st St, Suite 400, Mcallen, TX, 78503
Phone (956) 687-3937
Fax (956) 687-3938
Enumeration date Jul 14, 2006
Last updated in NPPES Aug 22, 2020

Taxonomy & classification

207W00000X Ophthalmology Physician Allopathic & Osteopathic Physicians · License K5972 (TX) Primary

Authorized official

Name Errol Grannum
Title Owner
Phone (956) 687-3937

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 is Errol O Grannum located?
The practice location on file with NPPES is in Mcallen, TX.
How current is this record?
Data comes from the CMS NPPES public dissemination file; this record was last updated in NPPES on 2020-08-22. Verify at npiregistry.cms.hhs.gov.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2020-08-22.