Thomas A Onstad, M.D.

Primary specialty

SpecialistTaxonomy code 174400000X

License

MD07372 Issued in OR

Practice address

923 Country Club Rd
Suite 100
Eugene, OR 97401-2296

Phone

(541) 343-1629

Fax

(541) 485-5944

NPI assigned

Dec 20, 2005

Sex

Male

Sole proprietor

No

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

Specialties & licenses 1

Addresses

Other identifiers 1

Medicare fee-for-service enrollment

Not listed in the public Medicare enrollment file

Medicare enrollment (NPD)

Not enrolled

Credentials

Doctor of Medicine

State licenses

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

{
    "created_epoch": "1135036800000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1783900800000",
    "number": "1639155773",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "923 COUNTRY CLUB RD",
            "address_2": "SUITE 100",
            "city": "EUGENE",
            "state": "OR",
            "postal_code": "974012296",
            "telephone_number": "541-343-1629",
            "fax_number": "541-485-5944"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "923 COUNTRY CLUB RD",
            "address_2": "SUITE 100",
            "city": "EUGENE",
            "state": "OR",
            "postal_code": "974012296",
            "telephone_number": "541-343-1629",
            "fax_number": "541-485-5944"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "ONSTAD",
        "first_name": "THOMAS",
        "middle_name": "A",
        "name_prefix": "Dr.",
        "credential": "M.D.",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2005-12-20",
        "last_updated": "2026-07-13",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "174400000X",
            "taxonomy_group": "",
            "desc": "Specialist",
            "state": "OR",
            "license": "MD07372",
            "primary": true
        }
    ],
    "identifiers": [
        {
            "code": "05",
            "desc": "MEDICAID",
            "issuer": null,
            "identifier": "141481",
            "state": "OR"
        }
    ],
    "endpoints": [],
    "other_names": []
}

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• Specialist in Eugene, OR
• Providers in Eugene, OR by specialty
• Specialist in Oregon

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Jul 13, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.