Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Dr. Mohammad Ali Abbass, MD

Individual provider Surgery Physician · NPI 1730508052

Dr. Mohammad Ali Abbass, MD is registered under Colorectal Surgery (Proctology) in Chicago, Illinois. Qualified in 2009, 17 years ago. Practices with MSK Nassau, a 98-clinician group, works from 2 locations, accepts Medicare assignment and offers telehealth. Licensed in Illinois and Ohio.

Years since qualifying
17
Licensed in
IL, OH
In the registry since
2014
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) 695-2729
Show map & directions

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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 9500 Euclid Ave, Cleveland, OH 44195-0001 — (818) 416-1777

Specialties & licences

Colon & Rectal Surgery Physician (primary) Taxonomy 208C00000X · Licence 036153116 (IL)
Surgery Physician Taxonomy 208600000X · Licence 35.133719 (OH)

Record details

NPI number1730508052
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorYes
NPI enumeratedApril 15, 2014
Last updated in NPPESOctober 7, 2020
Certification dateOctober 7, 2020

Medicare enrollment

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

Medicare specialtyCOLORECTAL SURGERY (PROCTOLOGY)
Also practisesMEDICAL GENETICS AND GENOMICS
Medical schoolOTHER
Graduated 2009 (17 years in practice)
Group practice Msk Nassau — 98 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations8 on file with Medicare

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.

Colonoscopy 73 times · 72nd percentile
Removal of skin lesions 1–10 times
Removal of tissue 1–10 times

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 patients86
Services billed 151 a service is one billed item, such as a visit, a test or a procedure
Average patient age73

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.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Consulting Fee $375 1 payment
Travel and Lodging $250 1 payment · travel or lodging paid or reimbursed, such as to attend a conference
Food and Beverage $176 2 payments · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Affiliated with 1 hospital, which CMS identifies by certification number only.

Colleagues at MSK Nassau

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 98 clinicians in the practice; 12 are shown here.

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