NPIMap

Individual provider Active NPI

Nicholas C. Ellefson, DO

  • Hospitalist Physician
  • Duluth, MN
National Provider Identifier
1639699200
Registry record updated Sep 1, 2026
On this page

Key facts

NPPES NPI Registry
Primary specialty
Hospitalist PhysicianTaxonomy code 208M00000X
License
66646 Issued in MN
Practice address
402 E 2ND St
Duluth, MN 55805-1906
Phone
(218) 786-4000
NPI assigned
Jun 23, 2017
Sex
Male
Sole proprietor
No

NPPES NPI Registry

Updated by the provider on Sep 1, 2026

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

Specialties & licenses 5

Specialty (taxonomy)CodeLicenseStatePrimary
Hospitalist Physician 208M00000X 71579-21 WI
Hospitalist Physician 208M00000X 66646 MN Primary
Family Medicine Physician 207Q00000X 66646 MN
Family Medicine Physician 207Q00000X 71579-21 WI
Family Medicine Physician 207Q00000X 3356 WV

Addresses

Primary practice location

402 E 2ND St
Duluth, MN 55805-1906

Mailing address

1702 University Dr S
Fargo, ND 58103-4940

Other practice location 1

3500 Tower Ave
Superior, WI 54880-4491
Phone (715) 817-7100

Medicare participation

Medicare enrollment files
Medicare fee-for-service enrollment
Enrolled in MN, WI2 enrollments
Eligible to order & refer
  • Part B services
  • Medical equipment
  • Home health
  • Power mobility devices
  • Hospice
Green means eligible to order or refer.

Enrollment records 2

Enrollment IDStateProvider typePAC IDDetails
I20200713003364 MN Practitioner - Hospitalist 5092089938 Reassigns benefits to 1 organization
I20201027002963 WI Practitioner - HospitalistPractitioner - Family Practice 5092089938 Reassigns benefits to 2 organizations

Care Compare profile

Medicare Care Compare
Specialty
HospitalistAlso: Family Practice
Education
West Virginia School of Osteopathic Medicine, 2012
Medicare assignment
Accepts the Medicare-approved amount as payment in full
Group practices
St Marys Hospital of SuperiorGroup PAC ID 8628964228, 96 clinicians
The Duluth Clinic LTDGroup PAC ID 2567374283, 1,135 clinicians

Practice addresses (Care Compare)

3500 Tower Ave
Superior, WI 54880-4491
Phone (715) 392-8281

400 E 3Rd St
Duluth, MN 55805-1951
Phone (218) 786-8364

Hospital & facility affiliations

  • Essentia Health St Mary'S Medical Center Hospital, Duluth, MN, CCN 240002
  • St Marys Hospital Superior Hospital, Superior, WI, CCN 521329
  • Essentia Health Duluth Hospital, Duluth, MN, CCN 240019
  • Essentia Health Moose Lake Hospital, Moose Lake, MN, CCN 241350
  • St Marys Hospital Superior Nursing home, CCN 52Z329

National Provider Directory

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

State licenses

LicenseStateTypeSpecialty
66646MNMDFamily Medicine Physician
71579-21WIMDFamily Medicine Physician
3356WVMDFamily Medicine Physician

Practice roles

OrganizationSpecialtyStatusNew patients
St. Mary'S Duluth Clinic Health System Current Accepting new patients
The Duluth Clinic LTD Current Accepting new patients
The Duluth Clinic, LTD. CurrentSince Aug 17, 2020 Accepting new patients
St. Mary'S Hospital of Superior CurrentSince Aug 17, 2020 Accepting new patients
St. Mary'S Hospital of Superior Current Accepting new patients
The Duluth Clinic, LTD CurrentSince Aug 17, 2020 Accepting new patients
St Marys Medical Center Past Accepting new patients

Locations

400 E 3rd St
Duluth, MN 55805
Phone (218) 722-8364

3500 Tower Ave
Superior, WI 54880
Phone (715) 392-8281

Organizations & group practices 7

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 7

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": "1498176000000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1788220800000",
    "number": "1639699200",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "1702 UNIVERSITY DR S",
            "city": "FARGO",
            "state": "ND",
            "postal_code": "581034940"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "402 E 2ND ST",
            "city": "DULUTH",
            "state": "MN",
            "postal_code": "558051906",
            "telephone_number": "218-786-4000"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "3500 Tower Ave",
            "address_purpose": "LOCATION",
            "city": "Superior",
            "state": "WI",
            "postal_code": "548804491",
            "country_code": "US",
            "telephone_number": "715-817-7100",
            "fax_number": "715-817-7039",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "ELLEFSON",
        "first_name": "NICHOLAS",
        "middle_name": "C.",
        "name_prefix": "Dr.",
        "credential": "DO",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2017-06-23",
        "last_updated": "2026-09-01",
        "certification_date": "2026-09-01",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "208M00000X",
            "taxonomy_group": "",
            "desc": "Hospitalist",
            "state": "WI",
            "license": "71579-21",
            "primary": false
        },
        {
            "code": "208M00000X",
            "taxonomy_group": "",
            "desc": "Hospitalist",
            "state": "MN",
            "license": "66646",
            "primary": true
        },
        {
            "code": "207Q00000X",
            "taxonomy_group": "",
            "desc": "Family Medicine",
            "state": "MN",
            "license": "66646",
            "primary": false
        },
        {
            "code": "207Q00000X",
            "taxonomy_group": "",
            "desc": "Family Medicine",
            "state": "WI",
            "license": "71579-21",
            "primary": false
        },
        {
            "code": "207Q00000X",
            "taxonomy_group": "",
            "desc": "Family Medicine",
            "state": "WV",
            "license": "3356",
            "primary": false
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

Other providers in Duluth, MN

Sources for this page

Verify at the official NPI Registry.