NPIMap

Individual provider Active NPI

Julia Alexa Ondarza, PA-C

  • Physician Assistant
  • Walnut Creek, CA
National Provider Identifier
1013537794
Registry record updated Oct 29, 2025
On this page

Key facts

NPPES NPI Registry
Primary specialty
Physician AssistantTaxonomy code 363A00000X
License
60191 Issued in CA
Practice address
2637 Shadelands Dr
Walnut Creek, CA 94598-2512
Phone
(925) 430-5335
Fax
(925) 430-5446
NPI assigned
Apr 22, 2020
Sex
Female
Sole proprietor
No

NPPES NPI Registry

Updated by the provider on Oct 29, 2025

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

Specialties & licenses 2

Specialty (taxonomy)CodeLicenseStatePrimary
Physician Assistant 363A00000X 60191 CA Primary
Medical Physician Assistant 363AM0700X 60191 CA

Addresses

Primary practice location

2637 Shadelands Dr
Walnut Creek, CA 94598-2512

Mailing address

2637 Shadelands Dr
Walnut Creek, CA 94598-2512
Phone (925) 430-5335

Other practice location 1

10120 S Eastern Ave Ste 120
Henderson, NV 89052-3952
Phone (702) 483-6200

Other practice location 2

300 Pasteur Dr
Stanford, CA 94305-2200
Phone (650) 723-4000

Medicare participation

Medicare enrollment files
Medicare fee-for-service enrollment
Enrolled in CA
Eligible to order & refer
  • Part B services
  • Medical equipment
  • Home health
  • Power mobility devices
  • Hospice
Green means eligible to order or refer.

Enrollment records 1

Enrollment IDStateProvider typePAC IDDetails
I20211111000412 CA Practitioner - Physician Assistant 0749600476 Reassigns benefits to 5 organizations

Care Compare profile

Medicare Care Compare
Specialty
Physician Assistant
Education
Other, 2019
Medicare assignment
Accepts the Medicare-approved amount as payment in full
Telehealth
Offers telehealth services
Group practices
Nextgen RPM LLCGroup PAC ID 1153666904, 6 clinicians
Brandon McCutcheon MD PCGroup PAC ID 5294198768, 5 clinicians
Stanford Health CareGroup PAC ID 6709797491, 3,152 clinicians

Practice addresses (Care Compare)

25775 McBean Pkwy
Suite 106
Santa Clarita, CA 91355-3702
Phone (972) 807-3696

2637 Shadelands Dr
Suite A2
Walnut Creek, CA 94598-2512
Phone (925) 430-5335

300 Pasteur Dr
Stanford, CA 94305-2200
Phone (650) 723-4000

Hospital & facility affiliations

  • Stanford Health Care Hospital, Stanford, CA, CCN 050441
  • John Muir Medical Center - Walnut Creek Campus Hospital, Walnut Creek, CA, CCN 050180

Merit-based Incentive Payment System (MIPS)

Final score
88.53 of 100Reported as group
Quality
87.08
Promoting interoperability
100
Improvement activities
40
Cost
69.51

National Provider Directory

National Provider Directory
Medicare enrollment (NPD)
Enrolled
Credentials
Physician Assistant

Practice roles

OrganizationSpecialtyStatusNew patients
Bass Medical Group CurrentSince Feb 1, 2024 Accepting new patients
Bass Medical Group CurrentSince Feb 1, 2024 Accepting new patients
Stanford Health Care CurrentSince Nov 8, 2021 Accepting new patients
Stanford Health Care CurrentSince Nov 8, 2021 Accepting new patients
Recovery Plus USA Inc. Past Accepting new patients
Bass Medical Group Past Accepting new patients
Bass Medical Group Past Accepting new patients
Bass Medical Group Past Accepting new patients

Locations

1505 Saint Alphonsus Way
Alamo, CA 94507
Phone (925) 837-4225

300 Pasteur Dr
Stanford, CA 94305
Phone (650) 498-5710

2637 Shadelands Dr
Ste A2
Walnut Creek, CA 94598
Phone (925) 430-5335

2637 Shadelands Dr
Walnut Creek, CA 94598
Phone (925) 627-3424

Interoperability endpoints

  • FHIR API: https://fhir4.healow.com/fhir/r4/IBDGCA
  • Direct secure messaging: jondarza171033@ehr.johnmuirhealth.com

Organizations & group practices 12

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.

Hospital & facility affiliations 8

Hospitals and other facilities this clinician is affiliated with according to Medicare Care Compare.

NPI Registry JSON

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

{
    "created_epoch": "1587513600000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1761696000000",
    "number": "1013537794",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "2637 SHADELANDS DR",
            "city": "WALNUT CREEK",
            "state": "CA",
            "postal_code": "945982512",
            "telephone_number": "925-430-5335",
            "fax_number": "925-430-5446"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "2637 SHADELANDS DR",
            "city": "WALNUT CREEK",
            "state": "CA",
            "postal_code": "945982512",
            "telephone_number": "925-430-5335",
            "fax_number": "925-430-5446"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "10120 S Eastern Ave Ste 120",
            "address_purpose": "LOCATION",
            "city": "Henderson",
            "state": "NV",
            "postal_code": "890523952",
            "country_code": "US",
            "telephone_number": "702-483-6200",
            "country_name": "United States",
            "address_type": "DOM"
        },
        {
            "address_1": "300 Pasteur Dr",
            "address_purpose": "LOCATION",
            "city": "Stanford",
            "state": "CA",
            "postal_code": "943052200",
            "country_code": "US",
            "telephone_number": "650-723-4000",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "ONDARZA",
        "first_name": "JULIA",
        "middle_name": "ALEXA",
        "credential": "PA-C",
        "sole_proprietor": "NO",
        "sex": "F",
        "enumeration_date": "2020-04-22",
        "last_updated": "2025-10-29",
        "certification_date": "2025-10-29",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "363A00000X",
            "taxonomy_group": "",
            "desc": "Physician Assistant",
            "state": "CA",
            "license": "60191",
            "primary": true
        },
        {
            "code": "363AM0700X",
            "taxonomy_group": "",
            "desc": "Physician Assistant, Medical",
            "state": "CA",
            "license": "60191",
            "primary": false
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

Other providers in Walnut Creek, CA

Sources for this page

Verify at the official NPI Registry.