Nickolas S Demark, DO

Primary specialty

Hospice and Palliative Medicine (Internal Medicine) PhysicianTaxonomy code 207RH0002X

License

DO-06639 Issued in IA

Practice address

1229 C Ave E
Oskaloosa, IA 52577-4246

Phone

(641) 672-3100

Fax

(641) 672-3381

NPI assigned

Jun 30, 2011

Sex

Male

Sole proprietor

No

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

Specialties & licenses 4

Addresses

Medicare fee-for-service enrollment

Enrolled in IA

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

Internal MedicineAlso: Hospice/Palliative Care

Education

Des Moines University of Osteopathic Medicine and Health Sciences, 2011

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

Mahaska County HospitalGroup PAC ID 2769388677, shared by 6 NPIs, 128 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• Mahaska Health Partnership Hospice Services Hospice, Oskaloosa, IA, CCN 161511
• Mahaska Health Partnership Hospital, Oskaloosa, IA, CCN 161379

Merit-based Incentive Payment System (MIPS)

Final score

94.81 of 100Reported as apm

Quality

85.98

Promoting interoperability

100

Improvement activities

40

Merit-based Incentive Payment System (MIPS)

Final score

94.81 of 100Reported as apm

Quality

85.98

Promoting interoperability

100

Improvement activities

40

Merit-based Incentive Payment System (MIPS)

Final score

94.81 of 100Reported as apm

Quality

85.98

Promoting interoperability

100

Improvement activities

40

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Osteopathy

State licenses

Practice roles

Locations

Interoperability endpoints

• Direct secure messaging: ndemark1212872@direct.unitypoint.org

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.

• Mahaska County Hospital

  • Critical Access Hospital
  • Oskaloosa, IA
  • NPI 1356320659
  Medicare reassignment NPD
• Mahaska County Hospital

  • Family Medicine Physician
  • Oskaloosa, IA
  • NPI 1407869852
  Medicare reassignment NPD
• St Luke'S Methodist Hospital

  • General Acute Care Hospital
  • Cedar Rapids, IA
  • NPI 1083708226
  NPD

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

• Mahaska County Hospital

  • Community Based Hospice Care Agency
  • Oskaloosa, IA
  • NPI 1003886110
  Care Compare affiliation
• Mahaska County Hospital

  • Critical Access Hospital
  • Oskaloosa, IA
  • NPI 1356320659
  Care Compare affiliation

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

{
    "created_epoch": "1309392000000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1782864000000",
    "number": "1114214004",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "1229 C AVE E",
            "city": "OSKALOOSA",
            "state": "IA",
            "postal_code": "525774298",
            "telephone_number": "641-672-3236"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "1229 C AVE E",
            "city": "OSKALOOSA",
            "state": "IA",
            "postal_code": "525774246",
            "telephone_number": "641-672-3100",
            "fax_number": "641-672-3381"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "1715 Dousman St",
            "address_purpose": "LOCATION",
            "city": "Green Bay",
            "state": "WI",
            "postal_code": "543033211",
            "country_code": "US",
            "telephone_number": "920-496-4700",
            "country_name": "United States",
            "address_type": "DOM"
        },
        {
            "address_1": "1726 Shawano Ave",
            "address_purpose": "LOCATION",
            "city": "Green Bay",
            "state": "WI",
            "postal_code": "543033216",
            "country_code": "US",
            "telephone_number": "920-496-4700",
            "country_name": "United States",
            "address_type": "DOM"
        },
        {
            "address_1": "130 2nd St",
            "address_purpose": "LOCATION",
            "city": "Neenah",
            "state": "WI",
            "postal_code": "549562883",
            "country_code": "US",
            "telephone_number": "920-729-2738",
            "fax_number": "920-729-3021",
            "country_name": "United States",
            "address_type": "DOM"
        },
        {
            "address_1": "900 Illinois Ave",
            "address_purpose": "LOCATION",
            "city": "Stevens Point",
            "state": "WI",
            "postal_code": "544813114",
            "country_code": "US",
            "telephone_number": "715-346-5000",
            "country_name": "United States",
            "address_type": "DOM"
        },
        {
            "address_1": "1818 N Meade St",
            "address_purpose": "LOCATION",
            "city": "Appleton",
            "state": "WI",
            "postal_code": "549113454",
            "country_code": "US",
            "telephone_number": "920-735-7645",
            "fax_number": "920-735-7618",
            "country_name": "United States",
            "address_type": "DOM"
        },
        {
            "address_1": "900 Illinois Ave",
            "address_purpose": "LOCATION",
            "city": "Stevens Point",
            "state": "WI",
            "postal_code": "544813114",
            "country_code": "US",
            "telephone_number": "715-346-5000",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "DEMARK",
        "first_name": "NICKOLAS",
        "middle_name": "S",
        "credential": "DO",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2011-06-30",
        "last_updated": "2026-07-01",
        "certification_date": "2026-07-01",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "208M00000X",
            "taxonomy_group": "",
            "desc": "Hospitalist",
            "state": "WI",
            "license": "62482",
            "primary": false
        },
        {
            "code": "207R00000X",
            "taxonomy_group": "",
            "desc": "Internal Medicine",
            "state": "WI",
            "license": "62482",
            "primary": false
        },
        {
            "code": "207R00000X",
            "taxonomy_group": "",
            "desc": "Internal Medicine",
            "state": "MI",
            "license": "5101019580",
            "primary": false
        },
        {
            "code": "207RH0002X",
            "taxonomy_group": "",
            "desc": "Internal Medicine, Hospice and Palliative Medicine",
            "state": "IA",
            "license": "DO-06639",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Jessica Daniel
• April Kay Davis, LMSW
• Angela Dawn Dawson, PHARM.D.
• Eric Chad De Boef, D.D.S.
• Rebecca J Deloach
• Chad Alan Derby, ATC
• Marcy Chilton Dewitt, LMSW
• Rebecca Dickinson
• Meredith Dobson, MSW
• Linda Sue Doolan, MS, RD, LD

• Hospice and Palliative Medicine (Internal Medicine) Physician in Oskaloosa, IA
• Providers in Oskaloosa, IA by specialty
• Hospice and Palliative Medicine (Internal Medicine) Physician in Iowa

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