Keith Flaherty, MD

Primary specialty

Medical Oncology PhysicianTaxonomy code 207RX0202X

License

241789 Issued in MA

Practice address

55 Fruit St
Lawrence House 202
Boston, MA 02114-2621

Phone

(617) 643-5817

Fax

(617) 724-3166

NPI assigned

Jul 4, 2006

Last updated

Apr 1, 2026By the provider in NPPES

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 3

Medicare fee-for-service enrollment

Enrolled in MA

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

Medical OncologyAlso: Internal Medicine

Education

Johns Hopkins University School of Medicine, 1997

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Telehealth

Offers telehealth services

Group practices

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

Massachusetts General Physicians Organization IncGroup PAC ID 2466365820, 3,494 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

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

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

State licenses

Practice roles

Locations

Interoperability endpoints

• Direct secure messaging: flaherty.keith.mgh@direct.partners.masshiway.net

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

• Massachusetts General Physicians Organization Inc

  • Dermatology Physician
  • Boston, MA
  • NPI 1801874573
  Medicare reassignment Care Compare group NPD
• The General Hospital Corporation

  • General Acute Care Hospital
  • Boston, MA
  • NPI 1023049236
  Medicare reassignment Care Compare group NPD
• General Hospital Corp

  dba Massachusetts General Hospital Outpatient Pharmacy

  • General Acute Care Hospital
  • Boston, MA
  • NPI 1508390014
  NPD
• Frederick Health Hospital Inc

  dba Frederick Health Hospital

  • General Acute Care Hospital
  • Frederick, MD
  • NPI 1538165527
  NPD (past)
• Pennsylvania Oncology Hematology Associates PC

  • Non-Pharmacy Dispensing Site
  • Philadelphia, PA
  • NPI 1154378867
  NPD (past)
• University of Penn - Medical Group

  • Cardiovascular Disease Physician
  • Philadelphia, PA
  • NPI 1093725145
  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": "1151971200000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1775001600000",
    "number": "1861422966",
    "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": "617-643-5817",
            "fax_number": "617-724-3166"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "55 FRUIT ST",
            "address_2": "LAWRENCE HOUSE 202",
            "city": "BOSTON",
            "state": "MA",
            "postal_code": "021142621",
            "telephone_number": "617-643-5817",
            "fax_number": "617-724-3166"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "75 Francis St",
            "address_purpose": "LOCATION",
            "city": "Boston",
            "state": "MA",
            "postal_code": "021156110",
            "country_code": "US",
            "telephone_number": "617-732-5500",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "FLAHERTY",
        "first_name": "KEITH",
        "credential": "MD",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2006-07-04",
        "last_updated": "2026-04-01",
        "certification_date": "2026-04-01",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207RX0202X",
            "taxonomy_group": "",
            "desc": "Internal Medicine, Medical Oncology",
            "state": "MA",
            "license": "241789",
            "primary": true
        }
    ],
    "identifiers": [
        {
            "code": "05",
            "desc": "MEDICAID",
            "issuer": null,
            "identifier": "110082653A",
            "state": "MA"
        },
        {
            "code": "01",
            "desc": "Other (non-Medicare)",
            "issuer": "MEDICARE ACD",
            "identifier": "001188202",
            "state": "MA"
        },
        {
            "code": "01",
            "desc": "Other (non-Medicare)",
            "issuer": "MEDICARE PTAN",
            "identifier": "001188201",
            "state": "MA"
        }
    ],
    "endpoints": [],
    "other_names": []
}

• Devon Flaherty
• Devon M Flaherty, M.D.
• Elizabeth N Flaherty, DPT
• Karen Marie Flaherty, MSN, APRN-BC
• Kathleen Flaherty, RN
• Madeline Flaherty, RN, FNP-BC
• Michael Ryan Flaherty, D.O.
• Patricia Ann Flaherty, ANP
• Robert F Flaherty, M.D.
• Siobhan Flaherty, NP

• Medical Oncology Physician in Boston, MA
• Providers in Boston, MA by specialty
• Medical Oncology Physician in Massachusetts

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Apr 1, 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.