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DR. MARK J DEN HARTOG DC
NPI 1023081155
Chiropractor in Eugene, OR

Active since February 09, 2006
225 E 4TH AVE, EUGENE, OR 97401(541) 762-4807 Get Directions Write a Review

NPPES record last updated: June 24, 2026. Verified against the NPPES registry weekly; last sync: November 08, 2026.

About Dr. Mark J Den Hartog Dc NPPES

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

DR. MARK J DEN HARTOG DC (NPI 1023081155) is an individual chiropractor in Eugene, Oregon, licensed in Oregon (6485) and active in the NPI registry since February 2006. He maintains 2 additional practice locations and is a graduate of Northwestern College Of Chiropractic (1992).

NPPES Registry Identity

NPI1023081155
Entity TypeIndividualMale
Primary Taxonomy111N00000X
Provider Legal NameDR. MARK J DEN HARTOGCredential: DC
Location Address225 E 4TH AVEEugene, OR 97401-2429
Mailing Address225 E 4th AveEugene, OR 97401-2429 · (541) 762-4807 · Fax (541) 795-8810
Phone(541) 762-4807
Sole ProprietorYes
Medical School CMSNorthwestern College Of ChiropracticGraduated 1992
Enumeration DateFebruary 9, 2006
Last NPPES UpdateJune 24, 2026
NPPES CertifiedJune 24, 2026
✔ NPI 1023081155 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyChiropractorChiropractic Providers
Taxonomy Code111N00000X
Licenses✔ Licensed in OR · 6485✔ Licensed in WA · 60741817
Definition
A provider qualified by a Doctor of Chiropractic (D.C.), licensed by the State and who practices chiropractic medicine -that discipline within the healing arts which deals with the nervous system and its relationship to the spinal column and its interrelationship with other body systems.
225 E 4TH AVE, Eugene, OR 97401
Open in Google Maps ↗

Secondary Practice Locations 2

Location 1114 1/2 E MonroePleasantville, IA 50225-7744 · Phone (515) 848-3334 · Fax (515) 848-3355
Location 21018 7th Ave SEOlympia, WA 98501-1512 · Phone (360) 459-8114 · Fax (360) 493-8742

Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Moda Health Plan, Inc..Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Mark J Den Hartog Dc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID7618910738
PECOS Enrollment IDI20251209004243

Medicare Billing Reassignment

Medicare enrollment records show Mark Den Hartog reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Umpqua Chiropractic PC
59 mi
Chiropractor
535 NE STEPHENS ST
Roseburg, OR 97470
  • Reassigned Medicare billing, Oregon enrollment
  • 4 clinicians in this Medicare group
NPI 1124644216 (541) 672-4807

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Other Providers at the Same Location NPPES 2

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

UMPQUA CHIROPRACTIC PC
Chiropractor (Rehabilitation)
225 E 4TH AVE
EUGENE, OR 97401
Lane County (541) 672-4807
ASPEN INJURY CENTER LLC
Chiropractor
225 E 4TH AVE
EUGENE, OR 97401
Lane County (541) 762-4807

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 Mark Den Hartog's NPI number?

The NPI number for Mark Den Hartog is 1023081155. It was assigned to this individual provider in the NPPES registry on February 9, 2006.

Where is Mark Den Hartog located?

Mark Den Hartog practices at 225 E 4th Ave, Eugene, OR 97401. The listed phone number is (541) 762-4807.

What is Mark Den Hartog's specialty?

The primary specialty registered for this NPI is Chiropractor with taxonomy code 111N00000X.

Is Mark Den Hartog enrolled in Medicare?

Yes. Mark Den Hartog is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Mark Den Hartog's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Mark Den Hartog reassigns Medicare benefits to Umpqua Chiropractic PC (Roseburg, OR). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Mark Den Hartog's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Mark Den Hartog accept?

Health plans from Moda Health Plan, Inc. list Mark Den Hartog 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.

When was this NPI record last updated?

The NPPES record for Mark Den Hartog was last updated on June 24, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 months 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.