Dr Mark Tony Williams, MD - Medicare Ophthalmology in Santa Ana, CA

Dr Mark Tony Williams, MD is a medicare enrolled "Ophthalmology - Retina Specialist" physician in Santa Ana, California. He went to University Of California, San Francisco School Of Medicine and graduated in 2017 and has 7 years of diverse experience with area of expertise as Ophthalmology. He is a member of the group practice Orange County Retina Medical Group and his current practice location is 999 N Tustin Ave Ste 17, Santa Ana, California. You can reach out to his office (for appointments etc.) via phone at (714) 972-8432.

Dr Mark Tony Williams is licensed to practice in Oklahoma (license number 37829) and he also participates in the medicare program. He accepts medicare assignments (which means he accepts the Medicare-approved amount; you will not be billed for any more than the Medicare deductible and coinsurance) and his NPI Number is 1780118802.

Contact Information

Dr Mark Tony Williams, MD
999 N Tustin Ave Ste 17,
Santa Ana, CA 92705-6504
(714) 972-8432
(714) 560-8402

Map and Direction




Physician's Profile

Full NameDr Mark Tony Williams
GenderMale
SpecialityOphthalmology
Experience7 Years
Location999 N Tustin Ave Ste 17, Santa Ana, California
Accepts Medicare AssignmentsYes. He accepts the Medicare-approved amount; you will not be billed for any more than the Medicare deductible and coinsurance.
  Medical Education and Training:
  • Dr Mark Tony Williams attended and graduated from University Of California, San Francisco School Of Medicine in 2017
  NPI Data:
  • NPI Number: 1780118802
  • Provider Enumeration Date: 04/14/2017
  • Last Update Date: 11/06/2023
  Medicare PECOS Information:
  • PECOS PAC ID: 0941552640
  • Enrollment ID: I20230803003713

Medical Identifiers

Medical identifiers for Dr Mark Tony Williams such as npi, medicare ID, medicare PIN, medicaid, etc.
IdentifierTypeStateIssuer
1780118802NPI-NPPES

Medical Taxonomies and Licenses

TaxonomyTypeLicense (State)Status
207WX0107XOphthalmology - Retina Specialist 37829 (Oklahoma)Primary

Group Practice Association

Group Practice NameGroup PECOS PAC IDNo. of Members
Orange County Retina Medical Group19513458835

Medicare Reassignments

Some practitioners may not bill the customers directly but medicare billing happens through clinics / group practice / hospitals where the provider works. Medicare reassignment of benefits is a mechanism by which practitioners allow third parties to bill and receive payment for medicare services performed by them. Dr Mark Tony Williams allows following entities to bill medicare on his behalf.
Entity NameOrange County Retina Medical Group
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1750398863
PECOS PAC ID: 1951345883
Enrollment ID: O20050613000472

Medicare Part D Prescriber Enrollment

Any physician or other eligible professional who prescribes Part D drugs must either enroll in the Medicare program or opt out in order to prescribe drugs to their patients with Part D prescription drug benefit plans. Dr Mark Tony Williams is enrolled with medicare and thus, if eligible, can prescribe medicare part D drugs to patients with medicare part D benefits.

Mailing Address and Practice Location

Mailing AddressPractice Location Address
Dr Mark Tony Williams, MD
999 N Tustin Ave Ste 17,
Santa Ana, CA 92705-6504

Ph: (714) 972-8432
Dr Mark Tony Williams, MD
999 N Tustin Ave Ste 17,
Santa Ana, CA 92705-6504

Ph: (714) 972-8432

Reviews and Comments


Ophthalmology Doctors in Santa Ana, CA

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Dr. Timothy T You, M.D.
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Dr. Michael Bruce Lappin, MD
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Practice Location: 801 N Tustin Ave, Suite 700, Santa Ana, CA 92705
Phone: 714-541-4185    Fax: 714-541-3465
Noor Amra, M.D.
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Phone: 888-988-2800    

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Medicare Assignment: Assignment means that your doctor, provider, or supplier agrees (or is required by law) to accept the Medicare-approved amount as full payment for covered services. Most doctors, providers, and suppliers accept assignment, but you should always check to make sure. Participating providers have signed an agreement to accept assignment for all Medicare-covered services.

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