Ahmad Nassar, MD
NPI 1861988222 · Hematology & Oncology Physician · Chicago, IL
Enrolled with Medicare as Practitioner - Hematology/Oncology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Ahmad Nassar, MD is a Hematology & Oncology Physician provider in Chicago, IL (NPI 1861988222).
Provider details
- NPI number
- 1861988222
- Entity type
- Individual
- Primary specialty
- Hematology & Oncology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- Yes
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Student, Health Care
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
7 yrs in NPPES registry
- Profile completeness38% of score
83% 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
- 2018-07-09
- Last updated
- 2025-05-20
- Certified
- 2025-05-20
Frequently asked questions
- What is Ahmad Nassar's NPI number?
- Ahmad Nassar's National Provider Identifier (NPI) is 1861988222, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Ahmad Nassar's specialty?
- Ahmad Nassar is listed in the NPPES registry with a primary specialty of Hematology & Oncology Physician (Allopathic & Osteopathic Physicians).
- Where is Ahmad Nassar located?
- Ahmad Nassar's practice location on file with NPPES is 840 S Wood St Ste 820-E, Chicago, IL 60612-4325.
- What is Ahmad Nassar's phone number?
- The practice phone number listed in the NPPES registry for Ahmad Nassar is (312) 996-9424.
- Does Ahmad Nassar accept Medicare?
- Ahmad Nassar is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Ahmad Nassar's NPI active?
- Yes — Ahmad Nassar's NPI (1861988222) is active in the NPPES registry as of the last update on 2025-05-20.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.