MARK JONATHAN OLDENBURG LPC
NPI 1275261935
Counselor - Professional in Slinger, WI
About Mark Jonathan Oldenburg Lpc NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MARK JONATHAN OLDENBURG LPC (NPI 1275261935) is an individual professional provider in Slinger, Wisconsin, licensed in Wisconsin (12445) and active in the NPI registry since August 2022. He is enrolled in Medicare PECOS and is a graduate of Other (2023).
NPPES Registry Identity
Specialties & Licenses
Accepted Insurance
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Mark Jonathan Oldenburg Lpc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignment
Medicare enrollment records show Mark Oldenburg reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Juneau, WI 53039
- Reassigned Medicare billing, Wisconsin enrollment
- 14 clinicians in this Medicare group
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.
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 Oldenburg's NPI number?
The NPI number for Mark Oldenburg is 1275261935. It was assigned to this individual provider in the NPPES registry on August 10, 2022.
Where is Mark Oldenburg located?
Mark Oldenburg practices at 4509 Arthur Rd, Slinger, WI 53086. The listed phone number is (414) 966-7136.
What is Mark Oldenburg's specialty?
The primary specialty registered for this NPI is Counselor, specializing in Professional, with taxonomy code 101YP2500X.
Is Mark Oldenburg enrolled in Medicare?
Yes. Mark Oldenburg is registered in the Medicare PECOS enrollment system.
Which organization bills Medicare for Mark Oldenburg's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Mark Oldenburg reassigns Medicare benefits to County Of Dodge (Juneau, WI). 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 Oldenburg's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Mark Oldenburg accept?
Health plans from Quartz list Mark Oldenburg 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 Oldenburg was last updated on September 3, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 56 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.
# Mark Jonathan Oldenburg, LPC · NPI 1275261935
Professional provider in Slinger, Wisconsin. Individual provider, active in the CMS NPPES registry since August 10, 2022.
## Identity
- **NPI:** 1275261935 (Entity type: Individual)
- **Enumerated:** August 10, 2022
- **Primary specialty:** Counselor - Professional · taxonomy 101YP2500X
- **State license:** 12445 (Wisconsin)
- **Sole proprietor:** No
## Practice location
- **Address:** 4509 ARTHUR RD, Slinger, WI 53086-9603
- **Phone:** (414) 966-7136
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment
- **Bills Medicare through:** County Of Dodge (NPI 1871508515, Juneau, WI), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2023
## Record status
- **NPPES last updated:** September 3, 2026
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Source: [NPI Profile](https://npiprofile.com/npi/1275261935) · Data from the CMS NPPES public registry.