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GARY S OLSEN PHD
NPI 1437232154
Clinical Neuropsychologist in Marshfield, WI

Active since October 24, 2006PECOS Enrolled
1000 N OAK AVE, MARSHFIELD, WI 54449(715) 387-5511 Get Directions Write a Review

NPPES record last updated: May 8, 2023. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Gary S Olsen Phd NPPES

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

GARY S OLSEN PHD (NPI 1437232154) is an individual clinical neuropsychologist in Marshfield, Wisconsin, licensed in Wisconsin (2641) and active in the NPI registry since October 2006. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1437232154
Entity TypeIndividualMale
Primary Taxonomy103G00000X
Provider Legal NameGARY S OLSENCredential: PHD
Location Address1000 N OAK AVEMarshfield, WI 54449-5703
Mailing Address1000 N Oak AveMarshfield, WI 54449-5703 · (715) 387-5511
Phone(715) 387-5511
Sole ProprietorNo
Enumeration DateOctober 24, 2006
Last NPPES UpdateMay 8, 2023
NPPES CertifiedMay 8, 2023
✔ NPI 1437232154 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyClinical NeuropsychologistBehavioral Health & Social Service Providers
Taxonomy Code103G00000X
License✔ Licensed in WI · 2641
Definition
A clinical psychologist who applies principles of assessment and intervention based upon the scientific study of human behavior as it relates to normal and abnormal functioning of the central nervous system. The specialty is dedicated to enhancing the understanding of brain-behavior relationships and the application of such knowledge to human problems.
Also ListedPsychologistTaxonomy 103T00000X · License 2641 (WI)
1000 N OAK AVE, Marshfield, WI 54449
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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Anthem Blue Cross and Blue Shield, HealthPartners, Sanford Health Plan and more.Insurance ›

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Gary S Olsen Phd is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

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.

Medicare Billing Reassignments

2

Medicare enrollment records show Gary Olsen reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Marshfield Clinic Inc
Same address
Clinic/Center
1000 N OAK AVE
Marshfield, WI 54449
  • Reassigned Medicare billing, Wisconsin enrollment
  • 2,540 clinicians in this Medicare group
NPI 1952347981 (715) 387-5511
Mchs Hospitals Inc
Same address
Clinic/Center
1000 N OAK AVE
Marshfield, WI 54449
  • Reassigned Medicare billing, Wisconsin enrollment
  • 2,476 clinicians in this Medicare group
NPI 1093221434 (715) 387-5511

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 20

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

ALISON RAE SAMPSON D.O.
Obstetrics & Gynecology
1000 N OAK AVE
MARSHFIELD, WI 54449
Wood County (715) 387-5161
TAMARA L. LEAHY NP
Nurse Practitioner
1000 N OAK AVE
MARSHFIELD, WI 54449
Wood County (800) 782-8581
SAMANTHA ELAINE MOORE RD, CD, CDCES
Dietitian, Registered
1000 N OAK AVE
MARSHFIELD, WI 54449
Wood County (715) 389-7464
ROBERT BUNDY
Student in an Organized Health Care Education/Training Program
1000 N OAK AVE
MARSHFIELD, WI 54449
Wood County (715) 387-5511
EUGENE H. LARSON PA
Physician Assistant
1000 N OAK AVE
MARSHFIELD, WI 54449
Wood County (715) 387-5245
JAMES SKIBBA CRNA
Nurse Anesthetist, Certified Registered
1000 N OAK AVE
MARSHFIELD, WI 54449
Wood County (715) 387-7179
KENNETH E ENGELHART MD
Internal Medicine
1000 N OAK AVE
MARSHFIELD, WI 54449
Wood County (715) 387-5704
KRISTIN M GERNDT MD
Radiology (Vascular & Interventional Radiology)
1000 N OAK AVE
MARSHFIELD, WI 54449
Wood County (715) 389-3474

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 Gary Olsen's NPI number?

The NPI number for Gary Olsen is 1437232154. It was assigned to this individual provider in the NPPES registry on October 24, 2006.

Where is Gary Olsen located?

Gary Olsen practices at 1000 N Oak Ave, Marshfield, WI 54449. The listed phone number is (715) 387-5511.

What is Gary Olsen's specialty?

The primary specialty registered for this NPI is Clinical Neuropsychologist with taxonomy code 103G00000X.

Is Gary Olsen enrolled in Medicare?

Yes. Gary Olsen is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Gary Olsen's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Gary Olsen reassigns Medicare benefits to 2 organizations: Marshfield Clinic Inc (Marshfield, WI) and Mchs Hospitals Inc (Marshfield, WI). Each 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 Gary Olsen's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Gary Olsen accept?

Health plans from Anthem Blue Cross and Blue Shield, HealthPartners, Sanford Health Plan, Security Health Plan and UnitedHealthcare list Gary Olsen 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 Gary Olsen was last updated on May 8, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 years 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.