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Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

NICKOLAS S DEMARK DO
NPI 1114214004
Internal Medicine - Hospice and Palliative Medicine in Oskaloosa, IA

Active since June 30, 2011PECOS EnrolledAccepts Medicare Assignment
94.61/100
CMS Quality Rating
1229 C AVE E, OSKALOOSA, IA 52577(641) 672-3100(641) 672-3381 Get Directions Write a Review

NPPES record last updated: July 1, 2026. Verified against the NPPES registry weekly; last sync: August 09, 2026.

Record update history: Sep 11, 2025, Aug 16, 2024, May 20, 2021 and 2 more (5 updates tracked since 2018).

About Nickolas S Demark Do NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

NICKOLAS S DEMARK DO (NPI 1114214004) is an individual hospice and palliative medicine provider in Oskaloosa, Iowa, licensed in Iowa (DO-06639) and active in the NPI registry since June 2011. He is enrolled in Medicare PECOS, is affiliated with Mahaska Health Partnership, and maintains 5 additional practice locations.

NPPES Registry Identity

NPI1114214004
Entity TypeIndividualMale
Primary Taxonomy207RH0002X
Provider Legal NameNICKOLAS S DEMARKCredential: DO
Location Address1229 C AVE EOskaloosa, IA 52577-4246
Mailing Address1229 C Ave EOskaloosa, IA 52577-4298 · (641) 672-3236
Phone(641) 672-3100
Fax(641) 672-3381
Sole ProprietorNo
Medical School CMSDes Moines University Of Osteopathic Medicine And Health SciencesGraduated 2011
Enumeration DateJune 30, 2011
Last NPPES UpdateJuly 1, 20265 updates tracked since enumeration
NPPES CertifiedJuly 1, 2026
✔ NPI 1114214004 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 3

★ Primary SpecialtyInternal Medicine · Hospice and Palliative MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207RH0002X
License✔ Licensed in IA · DO-06639
Definition
An internal medicine physician with special knowledge and skills to prevent and relieve the suffering experienced by patients with life-limiting illnesses. This specialist works with an interdisciplinary hospice or palliative care team to maximize quality of life while addressing physical, psychological, social and spiritual needs of both patient and family throughout the course of the disease, through the dying process, and beyond for the family. This specialist has expertise in the assessment of patients with advanced disease; the relief of distressing symptoms; the coordination of interdisciplinary patient and family-centered care in diverse venues; the use of specialized care systems including hospice; the management of the imminently dying patient; and legal and ethical decision making in end-of-life care.
Also ListedInternal MedicineTaxonomy 207R00000X · License 62482 (WI), 5101019580 (MI)
Also ListedHospitalistTaxonomy 208M00000X · License 62482 (WI)
1229 C AVE E, Oskaloosa, IA 52577
Open in Google Maps ↗

Secondary Practice Locations 5

Location 11715 Dousman StGreen Bay, WI 54303-3211 · Phone (920) 496-4700
Location 21726 Shawano AveGreen Bay, WI 54303-3216 · Phone (920) 496-4700
Location 3130 2nd StNeenah, WI 54956-2883 · Phone (920) 729-2738 · Fax (920) 729-3021
Location 4900 Illinois AveStevens Point, WI 54481-3114 · Phone (715) 346-5000
Location 51818 N Meade StAppleton, WI 54911-3454 · Phone (920) 735-7645 · Fax (920) 735-7618

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter from Home State Health, Ambetter from NH Healthy Families, Ambetter from Sunflower Health Plan and more.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Nickolas S Demark Do is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID4880825363
PECOS Enrollment IDI20251022002524
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Areas of Expertise CMS Part B claims

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 99222
Initial hospital inpatient care is a service where a healthcare provider spends about 50 minutes per day overseeing your care while you're admitted in the hospital. This includes reviewing your health status, planning your treatment, and ensuring your safety and comfort.
41 services41 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Mahaska Health Partnership

Critical Access Hospitals · Oskaloosa, IA
4/5 CMS rating
OwnershipGovernment - Local
CMS Certification Number161379
Location1229 C Avenue EastOskaloosa, IA 52577 · Mahaska County
Emergency services Birthing friendly

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

94.61/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored through an Alternative Payment Model
Quality85.17
Promoting Interoperability100
Improvement Activities40

Referred Medical Equipment & Supplies CMS DME claims 2

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Oxygen concentrator, single delivery port, capable of delivering 85 percent or greater oxygen concentration at the prescribed flow rate E1390
DME-Oxygen and Supplies · category DC002N
2 suppliers16 claims16 services$92.19 avg. paid by Medicare
Portable gaseous oxygen system, rental; home compressor used to fill portable oxygen cylinders; includes portable containers, regulator, flowmeter, humidifier, cannula or mask, and tubing K0738
DME-Oxygen and Supplies · category DC000N
1 supplier12 claims12 services$32.88 avg. paid by Medicare
Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

NICOLE HELM PTA
Physical Therapy Assistant
1229 C AVE E
OSKALOOSA, IA 52577
Mahaska County (641) 672-3306
MR. PHIL T PORTER PSYCHOLOGIST
Psychologist
1229 C AVE E, #300
OSKALOOSA, IA 52577
Mahaska County (641) 672-3159
MATTHEW D. OLSON M.D.
Family Medicine
1229 C AVE E
OSKALOOSA, IA 52577
Mahaska County (641) 672-3100
MATTHEW M WILLIS CRNA
Nurse Anesthetist, Certified Registered
1229 C AVE E
OSKALOOSA, IA 52577
Mahaska County (641) 672-3360
BAILEY R TERPSTRA LAT, ATC
Specialist/Technologist (Athletic Trainer)
1229 C AVE E
OSKALOOSA, IA 52577
Mahaska County (641) 672-3274
STEFANIE YEARIAN ARNP
Nurse Practitioner (Psychiatric/Mental Health)
1229 C AVE E
OSKALOOSA, IA 52577
Mahaska County (641) 672-3259
DR. PATRICIA ANN KINNE M.D.
Psychiatry & Neurology (Psychiatry)
1229 C AVE E
OSKALOOSA, IA 52577
Mahaska County (502) 852-1033
CHRISTINE BEAIRD
Nurse Practitioner (Family)
1229 C AVE E
OSKALOOSA, IA 52577
Mahaska County (641) 672-3100

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Nickolas Demark's NPI number?

The NPI number for Nickolas Demark is 1114214004. It was assigned to this individual provider in the NPPES registry on June 30, 2011.

Where is Nickolas Demark located?

Nickolas Demark practices at 1229 C Ave E, Oskaloosa, IA 52577. The listed phone number is (641) 672-3100.

What is Nickolas Demark's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hospice and Palliative Medicine, with taxonomy code 207RH0002X.

Is Nickolas Demark enrolled in Medicare?

Yes. Nickolas Demark is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

What insurance does Nickolas Demark accept?

Health plans from Ambetter Health, Ambetter Health of Delaware, Ambetter from Home State Health, Ambetter from NH Healthy Families and Ambetter from Sunflower Health Plan list Nickolas Demark as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Nickolas Demark affiliated with any hospitals?

According to CMS data, Nickolas Demark is affiliated with Mahaska Health Partnership.

When was this NPI record last updated?

The NPPES record for Nickolas Demark was last updated on July 1, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 42 days ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.