Doctor profile · Federal record

Dr. William Riles, M.D.

Gastroenterology Physician (CMS: Gastroenterology) · Internal Medicine Physician · Gastroenterology Physician · Gastroenterology Physician · Chicago, IL

  • NPI 1891705737
  • Accepts Medicare
  • MIPS 78.2 / 100 · 2023
  • 28 yrs in practice
  • Licensed in 3 states
  • Male
  • Group practice
  • No sanctions

Practice & contact

Operates at 2 locations .

NPPES Updated May 11, 2026
Primary practice
1901 W Harrison St
Chicago, IL 606123714
(312) 864-7344
fax (312) 864-9624
Additional location
300 S 8Th St Ste 509E
Murray, KY 420712403
(270) 759-4000
fax (270) 752-2857

Credentials & registration

NPPES · NUCC
NPI registered
August 2006 — 20 yrs on file
Profile last updated
March 15, 2024
Year of graduation
1998 — 28 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State licenses (3)
Illinois #036-104745 · Kentucky #35093 · South Carolina #29567

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1891705737. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
13
Distinct HCPCS
1
Medicare allowed
$1,817
HCPCS Description Services Patients Avg allowed
99222 Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 13 13 $140

In context: peer comparison

Among 70 peers in Chicago Gastroenterology Physician, average services per provider: 239. This provider delivers 0.1× the peer median.

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
15
Patients
14
Total drug cost
$261
Drug Type Claims Patients Total cost
Peg-3350 and Electrolytes (Peg3350/Sod Sulf,Bicarb,Cl/Kcl) Brand 15 14 $261

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. William Riles's medical specialty?
Dr. William Riles practices Gastroenterology Physician in Chicago, IL.
Where does Dr. William Riles practice?
Dr. William Riles practices at 1901 W Harrison St, Chicago, IL 606123714. Office phone: 3128647344.
What is Dr. William Riles's NPI?
Dr. William Riles's National Provider Identifier (NPI) is 1891705737, issued by NPPES.
Does Dr. William Riles accept Medicare assignment?
Yes. Dr. William Riles accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. William Riles commonly perform?
Top Medicare-reported procedures in 2023: Initial hospital care with straightforward or low-level medical decision making (HCPCS 99222). Source: CMS Medicare Physician & Other Practitioners file.