John Koslosky II

Primary specialty

Physician AssistantTaxonomy code 363A00000X

Practice address

27401 W Highway 22 Ste 125
Barrington, IL 60010-5934

Phone

(847) 381-0388

Fax

(847) 381-0811

NPI assigned

Apr 18, 2023

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

Medicare fee-for-service enrollment

Enrolled in IL, WI2 enrollments

Eligible to order & refer

• Part B services: Yes
• Medical equipment: Yes
• Home health: Yes
• Power mobility devices: Yes
• Hospice: No

Green means eligible to order or refer.

Enrollment records 2

Specialty

Physician Assistant

Education

Other, 2025

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

Illinois Bone and Joint Institute, LLCGroup PAC ID 6002814878, 603 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• Advocate Good Shepherd Hospital Hospital, Barrington, IL, CCN 140291

Medicare enrollment (NPD)

Enrolled

Credentials

Physician Assistant

Practice roles

Locations

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.

• Illinois Bone and Joint Institute LLC

  • Orthopaedic Surgery Physician
  • Bannockburn, IL
  • NPI 1205922432

  WI

  Medicare reassignment Care Compare group NPD
• Illinois Bone and Joint Institute, LLC

  • Orthopaedic Surgery Physician
  • Arlington Heights, IL
  • NPI 1962219568
  NPD

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

• Advocate Health and Hospitals Corporation

  • General Acute Care Hospital
  • Barrington, IL
  • NPI 1447368071
  Care Compare affiliation

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

{
    "created_epoch": "1681776000000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1747785600000",
    "number": "1932895364",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "900 RAND RD STE 300",
            "city": "DES PLAINES",
            "state": "IL",
            "postal_code": "600162359",
            "telephone_number": "847-324-3976",
            "fax_number": "847-929-1154"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "27401 W HIGHWAY 22 STE 125",
            "city": "BARRINGTON",
            "state": "IL",
            "postal_code": "600105934",
            "telephone_number": "847-381-0388",
            "fax_number": "847-381-0811"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "KOSLOSKY",
        "first_name": "JOHN",
        "name_suffix": "II",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2023-04-18",
        "last_updated": "2025-05-21",
        "certification_date": "2025-05-21",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "363A00000X",
            "taxonomy_group": "",
            "desc": "Physician Assistant",
            "state": "IL",
            "license": null,
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Katherine Margaret Kleyn, RD
• Susan Harriett Koch, P.T.
• Patricia M Koltun, PSY.D.
• Madison Kornafel, DPT
• Daniel Korpela
• Lisa Maria Kowar, OD
• Violeta Kozlovskaja, APRN
• Heidi G Kramer, M.D.
• Cheryl Krautsak, LCPC
• Emily Krzyzanowsky, PTA

• Physician Assistant in Barrington, IL
• Providers in Barrington, IL by specialty
• Physician Assistant in Illinois

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on May 21, 2025; 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.