Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Ofer Fass, MD

Individual provider Internal Medicine Physician · NPI 1154856714

Ofer Fass, MD practises Gastroenterology in Chicago, Illinois. Graduated from Harvard Medical School in 2017, 9 years ago. Practices with Northwestern Medical Faculty Foundation, a 4,394-clinician group, works from 2 locations, accepts Medicare assignment and offers telehealth. Licensed in Illinois and New York.

Years since qualifying
9
Trained at
Harvard Medical School
Licensed in
IL, NY
In the registry since
2017
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

259 E Erie St Ste 1600
Chicago, IL 60611-3111
Phone: (312) 695-5620
Fax: (312) 695-2778
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 550 1st Ave, New York, NY 10016-6402 — (646) 929-7870

Specialties & licences

Gastroenterology Physician (primary) Taxonomy 207RG0100X · Licence 036170527 (IL)
Internal Medicine Physician Taxonomy 207R00000X · Licence 298903 (NY)

Record details

NPI number1154856714
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedApril 20, 2017
Last updated in NPPESDecember 17, 2024
Certification dateDecember 17, 2024

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyGASTROENTEROLOGY
Also practisesINTERNAL MEDICINE
Medical schoolHARVARD MEDICAL SCHOOL
Graduated 2017 (9 years in practice)
Group practice Northwestern Medical Faculty Foundation — 4394 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Upper gastrointestinal (GI) endoscopy for acid reflux 74 times · 71st percentile
Colonoscopy 26 times · 51st percentile

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients19
Services billed 29 a service is one billed item, such as a visit, a test or a procedure
Average patient age71

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at Northwestern Medical Faculty Foundation

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 4394 clinicians in the practice; 12 are shown here.

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