NPIMap

Individual provider Active NPI

Robert Paul Hasserjian, MD

  • Hematology (Pathology) Physician
  • Boston, MA
National Provider Identifier
1285625574
Registry record updated Jul 13, 2026
On this page

Key facts

NPPES NPI Registry
Primary specialty
Hematology (Pathology) PhysicianTaxonomy code 207ZH0000X
License
80560 Issued in MA
Practice address
55 Fruit St
WRN 225
Boston, MA 02114-2696
Phone
(617) 724-1445
Fax
(617) 726-7474
NPI assigned
Nov 4, 2005
Sex
Male
Sole proprietor
No

NPPES NPI Registry

Updated by the provider on Jul 13, 2026

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

Specialties & licenses 2

Specialty (taxonomy)CodeLicenseStatePrimary
Hematology (Pathology) Physician 207ZH0000X 80560 MA Primary
Anatomic Pathology Physician 207ZP0101X 80560 MA

Addresses

Primary practice location

55 Fruit St
WRN 225
Boston, MA 02114-2696

Mailing address

PO Box 9142
Charlestown, MA 02129-9142
Phone (617) 724-0287

Other identifiers 3

IdentifierTypeStateIssuer
3139514MedicaidMA
J31606OtherMABCBS MA
751191OtherMATUFTS HEALTH PLAN

Medicare participation

Medicare enrollment files
Medicare fee-for-service enrollment
Enrolled in MA
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
I20040712000532 MA Practitioner - Pathology 9335127760 Reassigns benefits to 3 organizations

Care Compare profile

Medicare Care Compare
Specialty
Pathology
Education
Harvard Medical School, 1990
Medicare assignment
Accepts the Medicare-approved amount as payment in full
Group practices

Practice addresses (Care Compare)

55 Fruit St
Boston, MA 02114-2696
Phone (617) 724-0287

75 Francis St
Boston, MA 02115-6110
Phone (617) 732-5500

Hospital & facility affiliations

National Provider Directory

National Provider Directory
Medicare enrollment (NPD)
Enrolled
Credentials
Doctor of Medicine

State licenses

LicenseStateTypeSpecialty
80560MAMDHematology (Pathology) Physician
19045ALMDPsychiatry Physician

Practice roles

OrganizationSpecialtyStatusNew patients
The General Hospital Corporation CurrentSince Oct 1, 2006 Accepting new patients
Brigham & Womens Physicians Organization Inc CurrentSince Nov 4, 2020 Accepting new patients
Massachusetts General Physicians Organization Inc CurrentSince Feb 1, 2001 Accepting new patients
General Hospital Corp Current Accepting new patients
Brigham and Womens Physicians Organization Inc Past Accepting new patients

Locations

75 Francis St
Boston, MA 02115

55 Fruit St
Ste 244
Boston, MA 02114

55 Fruit St
#2
Boston, MA 02114
Phone (617) 726-2967

55 Fruit St
#225
Boston, MA 02114
Phone (617) 726-2967

55 Fruit St
Boston, MA 02114

Interoperability endpoints

  • Direct secure messaging: hasserjian.robert.mgh@direct.partners.masshiway.net

Organizations & group practices 5

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 6

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": "1131062400000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1783900800000",
    "number": "1285625574",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "PO BOX 9142",
            "city": "CHARLESTOWN",
            "state": "MA",
            "postal_code": "021299142",
            "telephone_number": "617-724-0287",
            "fax_number": "617-726-2894"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "55 FRUIT ST",
            "address_2": "WRN 225",
            "city": "BOSTON",
            "state": "MA",
            "postal_code": "021142696",
            "telephone_number": "617-724-1445",
            "fax_number": "617-726-7474"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "HASSERJIAN",
        "first_name": "ROBERT",
        "middle_name": "PAUL",
        "name_prefix": "Dr.",
        "credential": "MD",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2005-11-04",
        "last_updated": "2026-07-13",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207ZH0000X",
            "taxonomy_group": "",
            "desc": "Pathology, Hematology",
            "state": "MA",
            "license": "80560",
            "primary": true
        },
        {
            "code": "207ZP0101X",
            "taxonomy_group": "",
            "desc": "Pathology, Anatomic Pathology",
            "state": "MA",
            "license": "80560",
            "primary": false
        }
    ],
    "identifiers": [
        {
            "code": "05",
            "desc": "MEDICAID",
            "issuer": null,
            "identifier": "3139514",
            "state": "MA"
        },
        {
            "code": "01",
            "desc": "Other (non-Medicare)",
            "issuer": "BCBS MA",
            "identifier": "J31606",
            "state": "MA"
        },
        {
            "code": "01",
            "desc": "Other (non-Medicare)",
            "issuer": "TUFTS HEALTH PLAN",
            "identifier": "751191",
            "state": "MA"
        }
    ],
    "endpoints": [],
    "other_names": []
}

Other providers in Boston, MA

Sources for this page

Verify at the official NPI Registry.