DR. WILLIAM LEWIS RILES M.D.
NPI 1891705737
Internal Medicine - Gastroenterology in Chicago, IL

Q: What is William Riles's NPI number?

The NPI number for William Riles is 1891705737. It was assigned to this individual provider in the NPPES registry on August 9, 2006.

Q: What is William Riles's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Q: When was this NPI record last updated?

The NPPES record for William Riles was last updated on March 15, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since August 09, 2006PECOS EnrolledAccepts Medicare Assignment

84.57/100

CMS Quality Rating

1901 W HARRISON ST, CHICAGO, IL 60612(312) 864-7344(312) 864-9624 Get Directions Write a Review

NPPES record last updated: March 15, 2024. Verified against the NPPES registry weekly; last sync: October 25, 2026.

On this page

About Dr. William Lewis Riles M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. WILLIAM LEWIS RILES M.D. (NPI 1891705737) is an individual gastroenterology provider in Chicago, Illinois, licensed in Illinois (036-104745) and active in the NPI registry since August 2006. He is enrolled in Medicare PECOS, is affiliated with Murray-calloway County Hospital, and maintains a secondary practice location in Murray.

NPPES Registry Identity

NPI1891705737

Entity TypeIndividualMale

Primary Taxonomy207RG0100X

Provider Legal NameDR. WILLIAM LEWIS RILESCredential: M.D.

Location Address1901 W HARRISON STChicago, IL 60612-3714

Mailing Address1901 W Harrison StChicago, IL 60612-3714 · (312) 864-7344 · Fax (312) 864-9624

Phone(312) 864-7344

Fax(312) 864-9624

Sole ProprietorNo

Medical School CMSUniversity Of South Carolina School Of MedicineGraduated 1998

Enumeration DateAugust 9, 2006

Last NPPES UpdateMarch 15, 2024

NPPES CertifiedMarch 15, 2024

✔ NPI 1891705737 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians

Taxonomy Code207RG0100X

Licenses✔ Licensed in IL · 036-104745✔ Licensed in KY · 35093✔ Licensed in SC · 29567

Definition

An internist who specializes in diagnosis and treatment of diseases of the digestive organs including the stomach, bowels, liver and gallbladder. This specialist treats conditions such as abdominal pain, ulcers, diarrhea, cancer and jaundice and performs complex diagnostic and therapeutic procedures using endoscopes to visualize internal organs.

Also ListedInternal MedicineTaxonomy 207R00000X · License 036-104745 (IL)

1901 W HARRISON ST, Chicago, IL 60612

Open in Google Maps ↗

Secondary Practice Location 1

Location 1300 S 8th St Ste 509EMurray, KY 42071-2403 · Phone (270) 759-4000 · Fax (270) 752-2857

Other Identifiers 1

Other1891705737IL · Medicare Npi

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. William Lewis Riles M.d. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID3678572500

PECOS Enrollment IDI20240403002729

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

Medicare enrollment records show William Riles reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Freeport Regional Health Care Foundation

104 mi

Family Medicine

1036 W STEPHENSON ST
Freeport, IL 61032

Reassigned Medicare billing, Illinois enrollment
391 clinicians in this Medicare group

NPI 1457337016 (815) 599-6000

Freeport Memorial Hospital

104 mi

General Acute Care Hospital

1045 W STEPHENSON ST
Freeport, IL 61032

Reassigned Medicare billing, Illinois enrollment
478 clinicians in this Medicare group

NPI 1447228788 (815) 599-6000

Murray-Calloway County Public Hospital Corporation

341 mi

Family Medicine

543 POWELL ST
Benton, KY 42025

Reassigned Medicare billing, Kentucky enrollment
99 clinicians in this Medicare group

NPI 1689813594 (270) 527-0045

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 3

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Biopsy of large bowel using a flexible endoscope 45380

A biopsy of the large bowel using a flexible endoscope is a procedure where a thin, flexible tube with a camera is inserted through the rectum to examine the bowel. If abnormal tissue is found, a small sample is taken for further examination. This helps in diagnosing conditions like inflammation, polyps, or cancer.

62 services61 patients

Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 43239

This procedure involves using a thin, flexible tube with a light and camera, known as an endoscope, to examine the esophagus, stomach, and upper part of the small intestine. Small tissue samples are taken for further examination to help diagnose various conditions.

46 services46 patients

Removal of polyps or growths of large bowel using an endoscope with mechanical snare 45385

This procedure involves using a thin, flexible tube called an endoscope to examine the large bowel. If any abnormal growths or polyps are found, a tool called a mechanical snare is used to remove them. This is a common method to prevent potential health issues.

20 services19 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Murray-Calloway County Hospital

Acute Care Hospitals · Murray, KY

1/5 CMS rating

OwnershipVoluntary non-profit - Other

CMS Certification Number180027

Location803 Poplar StreetMurray, KY 42071 · Calloway County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 60612 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient

$138.86 typical visit price

range $60.08 – $183.39

Typical copayment $34.71 (range $15.02 – $45.84)

Most-billed visit code 99204

Established Patient

$105.70 typical visit price

range $18.97 – $148.12

Typical copayment $26.42 (range $4.74 – $37.03)

Most-billed visit code 99214

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

84.57/100

MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program

Scored as part of a group practice

Quality

60.25

Promoting Interoperability

100

Improvement Activities

Cost

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

JOHANNA WEFES-POTTER

Emergency Medicine

1901 W HARRISON ST
CHICAGO, IL 60612

Cook County (847) 843-2000

ARON BERHANU GUDETTA MD

Internal Medicine

1901 W HARRISON ST
CHICAGO, IL 60612

Cook County (312) 864-6000

DR. LIGAYA VILLAFRANCA MARASIGAN M.D.

Obstetrics & Gynecology (Gynecology)

1901 W HARRISON ST
CHICAG, IL 60612

Cook County (312) 864-5901

TIN TIN THOMAS M.D.

Internal Medicine

1901 W HARRISON ST
CHICAGO, IL 60612

Cook County (312) 864-6000

COOK COUNTY

Pharmacy (Clinic Pharmacy)

1901 W HARRISON ST
CHICAGO, IL 60612

Cook County (312) 864-6189

HELEN ELIZABETH STRAUS MD

Emergency Medicine

1901 W HARRISON ST
CHICAGO, IL 60612

Cook County (312) 864-0060

MR. GLEN DERRICK TRAMMELL PA-C

Physician Assistant

1901 W HARRISON ST
CHICAGO, IL 60612

Cook County (773) 869-7488

JOHN H STROGER, JR. HOSPITAL OF COOK COUNTY

General Acute Care Hospital

1901 W HARRISON ST
CHICAGO, IL 60612

Cook County (773) 319-2085

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is William Riles's NPI number?

The NPI number for William Riles is 1891705737. It was assigned to this individual provider in the NPPES registry on August 9, 2006.

Where is William Riles located?

William Riles practices at 1901 W Harrison St, Chicago, IL 60612. The listed phone number is (312) 864-7344.

What is William Riles's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Is William Riles enrolled in Medicare?

Yes. William Riles is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organizations bill Medicare for William Riles's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Riles reassigns Medicare benefits to 3 organizations: Freeport Regional Health Care Foundation (Freeport, IL), Freeport Memorial Hospital (Freeport, IL) and Murray-Calloway County Public Hospital Corporation (Benton, KY). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for William Riles's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is William Riles affiliated with any hospitals?

According to CMS data, William Riles is affiliated with Murray-Calloway County Hospital.

When was this NPI record last updated?

The NPPES record for William Riles was last updated on March 15, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.