Kate Marie O'Brien, NP

Primary specialty

Nurse PractitionerTaxonomy code 363L00000X

License

RN273620 Issued in MA

Practice address

55 Fruit St
Boston, MA 02114-2621

Phone

(857) 367-1486

NPI assigned

Jan 27, 2010

Sex

Female

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 MA, CA2 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

Nurse Practitioner

Education

Other, 2009

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

The General Hospital CorporationGroup PAC ID 6507803806, 1,275 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• Massachusetts General Hospital Hospital, Boston, MA, CCN 220071

Medicare enrollment (NPD)

Enrolled

Credentials

Nurse Practitioner

State licenses

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.

• The General Hospital Corporation

  • General Acute Care Hospital
  • Boston, MA
  • NPI 1023049236
  Medicare reassignment Care Compare group
• Regents of the Univ of Ca

  • Maternal & Fetal Medicine Physician
  • Sacramento, CA
  • NPI 1013906973
  Medicare reassignment NPD
• Massachusetts General Physicians Organization Inc

  • Dermatology Physician
  • Boston, MA
  • NPI 1801874573
  Medicare reassignment
• Regents of the Univ of Ca

  • Diagnostic Radiology Physician
  • Sacramento, CA
  • NPI 1477546406
  NPD
• Regents of the University of Ca

  • Hematology (Internal Medicine) Physician
  • Sacramento, CA
  • NPI 1629061643
  NPD
• Beth Israel Deaconess Medical Center, Inc.

  • General Acute Care Hospital
  • Boston, MA
  • NPI 1548202641
  NPD (past)
• Regents of the Univ of Ca

  • Surgery Physician
  • Sacramento, CA
  • NPI 1427041698
  NPD (past)
• Regents of the Univ of Ca

  • Pulmonary Disease Physician
  • Sacramento, CA
  • NPI 1437142692
  NPD (past)

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

• The General Hospital Corporation

  • General Acute Care Hospital
  • Boston, MA
  • NPI 1023049236
  Care Compare affiliation

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

{
    "created_epoch": "1264550400000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1776038400000",
    "number": "1609107887",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "55 FRUIT ST",
            "city": "BOSTON",
            "state": "MA",
            "postal_code": "021142621",
            "telephone_number": "857-367-1486"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "55 FRUIT ST",
            "city": "BOSTON",
            "state": "MA",
            "postal_code": "021142621",
            "telephone_number": "857-367-1486"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "O'BRIEN",
        "first_name": "KATE",
        "middle_name": "MARIE",
        "credential": "NP",
        "sole_proprietor": "NO",
        "sex": "F",
        "enumeration_date": "2010-01-27",
        "last_updated": "2026-04-13",
        "certification_date": "2026-04-13",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "363L00000X",
            "taxonomy_group": "",
            "desc": "Nurse Practitioner",
            "state": "MA",
            "license": "RN273620",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Emma O'Brien
• Eva Louise O'Brien, MD
• Gail M O'Brien, MD
• James O'Brien, NP
• Julia B O'Brien
• Kayla Christine O'Brien, PHYSICIAN ASSISTANT
• Kayla Marie O'Brien, CNP
• Kerrilynn O'Brien
• Kerry L. O'Brien, M.D.
• Laura Beth O'Brien, SC.D.

• Nurse Practitioner in Boston, MA
• Providers in Boston, MA by specialty
• Nurse Practitioner in Massachusetts

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Apr 13, 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.