Mark Tony Williams, M.D.

Primary specialty

Retina Specialist (Ophthalmology) PhysicianTaxonomy code 207WX0107X

License

A187615 Issued in CA

Practice address

1310 W Stewart Dr Ste 303
Orange, CA 92868-3838

Phone

(714) 738-4621

Fax

(714) 409-0629

NPI assigned

Apr 14, 2017

Sex

Male

Sole proprietor

Yes

Registry information is reported by the provider to CMS and is not verified. About this source

Specialties & licenses 2

Addresses

Medicare fee-for-service enrollment

Enrolled in CA

Eligible to order & refer

• Part B services: Yes
• Medical equipment: Yes
• Home health: Yes
• Power mobility devices: Yes
• Hospice: Yes

Green means eligible to order or refer.

Enrollment records 1

Specialty

Ophthalmology

Education

University of California, San Francisco School of Medicine, 2017

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

Southern California Permanente Medical GroupGroup PAC ID 6002729175, 11,250 clinicians

Practice addresses (Care Compare)

Merit-based Incentive Payment System (MIPS)

Final score

99.93 of 100Reported as group

Quality

99.87

Improvement activities

40

Procedures performed for Medicare patients

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

State licenses

Practice roles

Locations

Networks

• BSC 65 PLUS INDIVIDUAL MAPD

Interoperability endpoints

• Direct secure messaging: mwilliams@retspecoc.intellechartdirect.net
• Direct secure messaging: mwilliams@ocretina.intellechartdirect.net
• Direct secure messaging: mwilliams71217@ouhealth.direct-ci.net

Organizations this provider is connected to: Medicare benefit reassignments (the organization bills Medicare for this provider’s services), Care Compare group memberships and National Provider Directory roles.

• Retina Specialists of Orange County, Inc.

  • Retina Specialist (Ophthalmology) Physician
  • Orange, CA
  • NPI 1629897517

  Multi-Specialty

  Medicare reassignment NPD Authorized official
• Southern California Permanente Medical Group

  • Health Maintenance Organization
  • Baldwin Park, CA
  • NPI 1770515280

  Multi-Specialty

  Medicare reassignment Care Compare group NPD
• Southern California Permanente Medical Group

  • Health Maintenance Organization
  • Santa Clarita, CA
  • NPI 1316409410
  NPD
• Southern California Permanente Medical Group

  • Health Maintenance Organization
  • Anaheim, CA
  • NPI 1952333460
  NPD
• Providence Medical Foundation

  • Family Medicine Physician
  • Brea, CA
  • NPI 1871607762

  Multi-Specialty

  NPD (past)

The complete NPPES record for this NPI in the NPI Registry API format.

{
    "created_epoch": "1492128000000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1787184000000",
    "number": "1780118802",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "PO BOX 104797",
            "city": "PASADENA",
            "state": "CA",
            "postal_code": "911890426",
            "telephone_number": "714-738-4621",
            "fax_number": "714-409-0629"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "1310 W STEWART DR STE 303",
            "city": "ORANGE",
            "state": "CA",
            "postal_code": "928683838",
            "telephone_number": "714-738-4621",
            "fax_number": "714-409-0629"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "WILLIAMS",
        "first_name": "MARK",
        "middle_name": "TONY",
        "name_prefix": "Dr.",
        "credential": "M.D.",
        "sole_proprietor": "YES",
        "sex": "M",
        "enumeration_date": "2017-04-14",
        "last_updated": "2026-08-20",
        "certification_date": "2026-08-20",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207WX0107X",
            "taxonomy_group": "193200000X MULTI-SPECIALTY GROUP",
            "desc": "Ophthalmology, Retina Specialist",
            "state": "CA",
            "license": "A187615",
            "primary": true
        },
        {
            "code": "207W00000X",
            "taxonomy_group": "193200000X MULTI-SPECIALTY GROUP",
            "desc": "Ophthalmology",
            "state": "CA",
            "license": "A187615",
            "primary": false
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Keaton Anthony Williams
• Kerry Michelle Williams, BC-FNP
• Landen Ramal Williams
• Laurie Beth Williams, CPNP
• Leon Williams
• Niesha Jasmine Dorea Williams
• Rosaura A Williams, MD
• Russell a Williams, MD
• Stephan Williams
• Teresa J Williams, LCSW

• Retina Specialist (Ophthalmology) Physician in Orange, CA
• Providers in Orange, CA by specialty
• Retina Specialist (Ophthalmology) Physician in California

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Aug 20, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• Medicare enrollment (CMS PECOS): enrollments, PAC IDs and benefit reassignments; Order and Referring.
• Medicare Care Compare (CMS): clinician profile, group practices, facility affiliations, MIPS scores and star ratings.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.