Dr. Errol O. Grannum
- Gender: Male
- Experience: 32 years
- Graduated from: Yale University School Of Medicine
- Graduation year: 1989
- Sole propriator: Yes
- NPI: 1508897935
Dr. Errol O. Grannum MD
Ophthalmologist
He is located at 1910 South 1st Street in McAllen, TX 78503. Can help patients with the following: Blepharitis, Esotropia, Eye Strain, Herpes of the Eye, Tunnel Vision, Usher Syndrome. His National Provider Identifier (NPI) number is 1508897935. Appointment can be made via the phone number (956) 687-3937. He is affiliated with 1 practices.
Conditions treated
Dr. Errol Olwyn Grannum, being an ophthalmologist, treats the following conditions. Please be advised that this list may not be complete. For the full list of conditions treated, consult directly with Dr. Errol O. Grannum.
- Astigmatism
- Binocular Dysfunction (BVD)
- Blepharitis
- Blindness
- Cataracts
- Chalazion
- Color Blindness
- Corneal Disease
- Corneal Ulcer
- Crossed Eyes
- Diabetic Retinopathy
- Double Vision
- Dry Eyes
- Esotropia
- Exotropia
- Eye Floaters
- Eye Strain
- Farsightedness
- Glaucoma
- Herpes of the Eye
- Hypertropia
- Keratitis
- Keratoconus
- LASIK
- Lazy Eye
- Macular Degeneration
- Nearsightedness
- Oculomotor Dysfunction
- Optic Neuritis
- Pink Eye
- Presbyopia
- Retinal Detachment
- Retinitis Pigmentosa (RP)
- Scleritis
- Sty
- Subconjunctival Hemorrhage
- Tunnel Vision
- Usher Syndrome
- Uveitis
Procedures Performed by Dr. Errol O. Grannum
ACA Marketplace (Obamacare/HealthCare.gov) plan networks
Insurers selling ACA Marketplace (HealthCare.gov) plans list Dr. Errol O. Grannum as in-network for the following 2026 plans.
Health plans
Ambetter from Superior HealthPlan
Network data as of Sep 15, 2026, as reported by the insurer.
Show all 12 plans from Ambetter from Superior HealthPlan
| Plan | Plan type | Network tier | New patients |
|---|---|---|---|
| Complete Gold | EPO · Gold | Preferred | Accepting new patients |
| Complete Gold + Vision + Adult Dental | EPO · Gold | Preferred | Accepting new patients |
| Enhanced Diabetes Care Silver with $0 Drug Options | EPO · Silver | Preferred | Accepting new patients |
| Enhanced Diabetes Care Silver with $0 Drug Options + Vision + Adult Dental | EPO · Silver | Preferred | Accepting new patients |
| Everyday Gold | EPO · Gold | Preferred | Accepting new patients |
| Everyday Gold + Vision + Adult Dental | EPO · Gold | Preferred | Accepting new patients |
| Focused Silver | EPO · Silver | Preferred | Accepting new patients |
| Focused Silver + Vision + Adult Dental | EPO · Silver | Preferred | Accepting new patients |
| Standard Gold | EPO · Gold | Preferred | Accepting new patients |
| Standard Gold + Vision + Adult Dental | EPO · Gold | Preferred | Accepting new patients |
| Standard Silver | EPO · Silver | Preferred | Accepting new patients |
| Standard Silver + Vision + Adult Dental | EPO · Silver | Preferred | Accepting new patients |
Blue Cross and Blue Shield of Texas
Network data as of Jun 7, 2026, as reported by the insurer.
Show all 19 plans from Blue Cross and Blue Shield of Texas
| Plan | Plan type | Network tier | New patients |
|---|---|---|---|
| Blue Advantage Bronze HMO℠ 204 (27 plan variants) | HMO · Expanded Bronze | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Bronze HMO℠ 301 (14 plan variants) | HMO · Bronze | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Bronze HMO℠ Standard (27 plan variants) | HMO · Expanded Bronze | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Gold HMO℠ 206 (27 plan variants) | HMO · Gold | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Gold HMO℠ 603 (14 plan variants) | HMO · Gold | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Gold HMO℠ Standard (27 plan variants) | HMO · Gold | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Plus Bronze℠ 303 (27 plan variants) | POS · Expanded Bronze | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Plus Bronze℠ 305 (27 plan variants) | POS · Bronze | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Plus Bronze℠ Standard (27 plan variants) | POS · Expanded Bronze | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Plus Gold℠ 203 (27 plan variants) | POS · Gold | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Plus Gold℠ 803 (27 plan variants) | POS · Gold | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Plus Gold℠ Standard (27 plan variants) | POS · Gold | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Plus Silver℠ 202 (27 plan variants) | POS · Silver | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Plus Silver℠ 605 (27 plan variants) | POS · Silver | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Plus Silver℠ Standard (27 plan variants) | POS · Silver | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Security HMO℠ 200 (27 plan variants) | HMO · Catastrophic | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Silver HMO℠ 205 (27 plan variants) | HMO · Silver | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Silver HMO℠ 801 (14 plan variants) | HMO · Silver | Blue Advantage HMO | Accepting new patients |
| Blue Advantage Silver HMO℠ Standard (27 plan variants) | HMO · Silver | Blue Advantage HMO | Accepting new patients |
WellPoint
Network data as of Sep 10, 2026, as reported by the insurer.
Show all 21 plans from WellPoint
| Plan | Plan type | Network tier | New patients |
|---|---|---|---|
| Wellpoint Essential Bronze 4000 HSA (+ Incentives) | HMO · Expanded Bronze | Participating | Accepting new patients |
| Wellpoint Essential Bronze 6000 ($0 Virtual PCP + $0 Select Drugs + Incentives) | HMO · Expanded Bronze | Participating | Accepting new patients |
| Wellpoint Essential Bronze 6000 Adult Dental/Vision ($0 Virtual PCP+$0 Select Drugs) | HMO · Expanded Bronze | Participating | Accepting new patients |
| Wellpoint Essential Bronze 7500 Standard ($0 Virtual PCP + $0 Select Drugs + Incentives) | HMO · Expanded Bronze | Participating | Accepting new patients |
| Wellpoint Essential Bronze POS 4500 ($0 Virtual PCP + $0 Select Drugs + Incentives) | POS · Expanded Bronze | Participating | Accepting new patients |
| Wellpoint Essential Bronze POS 5500 ($0 Virtual PCP + $0 Select Drugs + Incentives) | POS · Expanded Bronze | Participating | Accepting new patients |
| Wellpoint Essential Bronze POS 7500 Standard ($0 Virtual PCP + $0 Select Drugs + Incentives) | POS · Expanded Bronze | Participating | Accepting new patients |
| Wellpoint Essential Catastrophic (+ Incentives) | HMO · Catastrophic | Participating | Accepting new patients |
| Wellpoint Essential Gold 1500 ($0 Virtual PCP + $0 Select Drugs + Incentives) | HMO · Gold | Participating | Accepting new patients |
| Wellpoint Essential Gold 2000 Standard ($0 Virtual PCP + $0 Select Drugs + Incentives) | HMO · Gold | Participating | Accepting new patients |
| Wellpoint Essential Gold 800 ($0 Virtual PCP + $0 Select Drugs + Incentives) | HMO · Gold | Participating | Accepting new patients |
| Wellpoint Essential Gold POS 1000 ($0 Virtual PCP + $0 Select Drugs + Incentives) | POS · Gold | Participating | Accepting new patients |
| Wellpoint Essential Gold POS 2000 Standard ($0 Virtual PCP + $0 Select Drugs + Incentives) | POS · Gold | Participating | Accepting new patients |
| Wellpoint Essential Gold POS 700 ($0 Virtual PCP + $0 Select Drugs + Incentives) | POS · Gold | Participating | Accepting new patients |
| Wellpoint Essential Silver 1850 ($0 Virtual PCP + $0 Select Drugs + Incentives) | HMO · Silver | Participating | Accepting new patients |
| Wellpoint Essential Silver 3500 ($0 Virtual PCP + $0 Select Drugs + Incentives) | HMO · Silver | Participating | Accepting new patients |
| Wellpoint Essential Silver 3500 Adult Dental/Vision ($0 Virtual PCP + $0 Select Drugs + Incentives) | HMO · Silver | Participating | Accepting new patients |
| Wellpoint Essential Silver 6000 Standard ($0 Virtual PCP + $0 Select Drugs + Incentives) | HMO · Silver | Participating | Accepting new patients |
| Wellpoint Essential Silver POS 2500 ($0 Virtual PCP + $0 Select Drugs + Incentives) | POS · Silver | Participating | Accepting new patients |
| Wellpoint Essential Silver POS 4000 ($0 Virtual PCP + $0 Select Drugs + Incentives) | POS · Silver | Participating | Accepting new patients |
| Wellpoint Essential Silver POS 6000 Standard ($0 Virtual PCP + $0 Select Drugs + Incentives) | POS · Silver | Participating | Accepting new patients |
This covers ACA Marketplace plans only, as reported by each insurer. It does not include employer, Medicare Advantage, or state-run exchange plans, and a plan missing from this list does not mean Dr. Errol O. Grannum is out of network. Insurer directories can be out of date, so always confirm with the insurer and the office before your visit.
Medicare Enrollment
Dr. Errol O. Grannum is enrolled to bill Medicare as a Practitioner - Ophthalmology .
Bills through: Errol O Grannum
Based on Medicare's public enrollment records as of Jul 17, 2026. This reflects Medicare fee-for-service enrollment only and says nothing about other insurance, quality, outcomes, or board certification.
Payments received
Drug payment
| Allergan | $226 |
| Alcon | $134 |
| Bausch \u0026 Lomb a division of Bausch Health US LLC | $100 |
Other
| Food and Beverage | $463 |
| Promotional Speaking or Service | $21 |
Studies
YALE UNIVERSITY SCHOOL OF MEDICINE
Graduated in 1989
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Questions & Answers
Does Dr. Errol Olwyn Grannum have affiliation with practices?
Dr. Errol Olwyn Grannum is affiliated with Errol O Grannum.
What conditions does Dr. Errol Olwyn Grannum treat?
Dr. Errol Olwyn Grannum provides treatment for Blepharitis, Esotropia, Eye Strain, Herpes of the Eye, Tunnel Vision, Usher Syndrome. For the full list see this list.
Does Dr. Errol Olwyn Grannum accept patients with WellPoint?
Yes, Dr. Errol Olwyn Grannum is listed in-network for WellPoint through the ACA Marketplace (Obamacare/HealthCare.gov). See the Marketplace plans section for details.
Where can you meet with Dr. Errol Olwyn Grannum?
Dr. Errol Olwyn Grannum's office is located at 1910 South 1st Street in McAllen, TX 78503.