NPIMap

Organization Active NPI

Sagaponack Medical PC

Doing business as Halsey Dermatology

  • Medical Specialty Clinic/Center
  • Sag Harbor, NY
National Provider Identifier
1407351646
Registry record updated Jul 8, 2026
On this page

Key facts

NPPES NPI Registry
Primary specialty
Medical Specialty Clinic/CenterTaxonomy code 261QM2500X
Legal business name
SAGAPONACK MEDICAL PC
Doing business as
Halsey Dermatology
Sag Harbor Dermatology
Practice address
3350 Noyac Rd
Sag Harbor, NY 11963-1908
Phone
(631) 731-1099
NPI assigned
Mar 29, 2018
Last updated
Jul 8, 2026By the provider in NPPES
Organization subpart
No

NPPES NPI Registry

Updated by the provider on Jul 8, 2026

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

Authorized official

Name
Mark A. Halsey, MDNPI 1790070480
Title
President
Phone
(631) 731-1099

Authorized official NPPES reports the official by name only. The link goes to the one practitioner connected to this organization with that name.

Specialties & licenses 1

Specialty (taxonomy)CodeLicenseStatePrimary
Medical Specialty Clinic/Center 261QM2500X Primary

Addresses

Primary practice location

3350 Noyac Rd
Sag Harbor, NY 11963-1908

Mailing address

3350 Noyac Rd
Sag Harbor, NY 11963-1908
Phone (631) 731-1099

Other practice location 1

3330 Noyack Rd
Sag Harbor, NY 11963-1930
Phone (631) 731-1099

Other names 2

  • Halsey Dermatology Doing business as
  • Sag Harbor Dermatology Doing business as

Medicare participation

Medicare enrollment files
Medicare fee-for-service enrollment
Enrolled in NY

Enrollment records 1

Enrollment IDStateProvider typePAC IDDetails
O20180522001369 NY Part B Supplier - Clinic/Group Practice 2567727563 Receives reassigned benefits from 3 practitioners
Practice locations: Sag Harbor, NY

National Provider Directory

National Provider Directory

Practitioners & affiliated clinicians

Practitioners 5

Individual providers connected to this organization through Medicare benefit reassignment, Care Compare group membership or National Provider Directory roles, and the practitioner matching its NPPES authorized official.

NPI Registry JSON

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

{
    "created_epoch": "1522281600000",
    "enumeration_type": "NPI-2",
    "last_updated_epoch": "1783468800000",
    "number": "1407351646",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "3350 NOYAC RD",
            "city": "SAG HARBOR",
            "state": "NY",
            "postal_code": "119631908",
            "telephone_number": "631-731-1099"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "3350 NOYAC RD",
            "city": "SAG HARBOR",
            "state": "NY",
            "postal_code": "119631908",
            "telephone_number": "631-731-1099"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "3330 Noyack Rd",
            "address_purpose": "LOCATION",
            "city": "Sag Harbor",
            "state": "NY",
            "postal_code": "119631930",
            "country_code": "US",
            "telephone_number": "631-731-1099",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "organization_name": "SAGAPONACK MEDICAL PC",
        "organizational_subpart": "NO",
        "enumeration_date": "2018-03-29",
        "last_updated": "2026-07-08",
        "certification_date": "2026-07-08",
        "status": "A",
        "authorized_official_last_name": "HALSEY",
        "authorized_official_first_name": "MARK",
        "authorized_official_middle_name": "A.",
        "authorized_official_title_or_position": "PRESIDENT",
        "authorized_official_telephone_number": "631-731-1099",
        "authorized_official_credential": "MD"
    },
    "taxonomies": [
        {
            "code": "261QM2500X",
            "taxonomy_group": "",
            "desc": "Clinic/Center, Medical Specialty",
            "state": null,
            "license": null,
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": [
        {
            "organization_name": "Halsey Dermatology",
            "code": "3",
            "type": "Doing Business As"
        },
        {
            "organization_name": "Sag Harbor Dermatology",
            "code": "3",
            "type": "Doing Business As"
        },
        {
            "organization_name": "Sag Harbor Dermatology",
            "code": "3",
            "type": "Doing Business As"
        }
    ]
}

Other providers in Sag Harbor, NY

Sources for this page

  • NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Jul 8, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
  • Medicare enrollment (CMS PECOS): enrollments, PAC IDs and benefit reassignments.
  • National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.