John Olson, MD
NPI 1194835249 · Internal Medicine Physician · Marshfield, WI
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
John Olson, MD is a Internal Medicine Physician provider in Marshfield, WI (NPI 1194835249).
Provider details
- NPI number
- 1194835249
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 29284 (WI)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-08-30
- Last updated
- 2007-07-08
Frequently asked questions
- What is John Olson's NPI number?
- John Olson's National Provider Identifier (NPI) is 1194835249, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is John Olson's specialty?
- John Olson is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is John Olson located?
- John Olson's practice location on file with NPPES is 1000 N Oak Ave, Marshfield, WI 54449.
- What is John Olson's phone number?
- The practice phone number listed in the NPPES registry for John Olson is (715) 387-5755.
- Does John Olson accept Medicare?
- John Olson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is John Olson's NPI active?
- Yes — John Olson's NPI (1194835249) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.