Mary Nielson
NPI 1750043360 · Internal Medicine Physician · Chicago, IL
Enrolled with Medicare as Order and Referring Only - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mary Nielson is a Internal Medicine Physician provider in Chicago, IL (NPI 1750043360).
Provider details
- NPI number
- 1750043360
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Sex
- Female
- Sole proprietor
- Yes
- License
- 125.085540 (IL)
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
4 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
- 2021-10-11
- Last updated
- 2025-06-23
- Certified
- 2025-06-23
Frequently asked questions
- What is Mary Nielson's NPI number?
- Mary Nielson's National Provider Identifier (NPI) is 1750043360, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mary Nielson's specialty?
- Mary Nielson is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Mary Nielson located?
- Mary Nielson's practice location on file with NPPES is 251 E Huron St, Chicago, IL 60611-3055.
- What is Mary Nielson's phone number?
- The practice phone number listed in the NPPES registry for Mary Nielson is (312) 926-2000.
- Does Mary Nielson accept Medicare?
- Mary Nielson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mary Nielson's NPI active?
- Yes — Mary Nielson's NPI (1750043360) is active in the NPPES registry as of the last update on 2025-06-23.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.