Doctor profile · Federal record

Dr. William Chapman, MD

Colon & Rectal Surgery Physician (CMS: Colorectal Surgery (Proctology)) · Surgery Physician · Saint Louis, MO

  • NPI 1003297177
  • Accepts Medicare
  • MIPS 79.3 / 100 · 2023
  • 11 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
1044 N Mason RD, Div Surg Colon/Rectal, Ste 310
Saint Louis, MO 631416431
(314) 454-7177
fax (888) 425-7946
Mailing address
Po Box 7412011
Chicago, IL 606742011

Credentials & registration

NPPES · NUCC
NPI registered
June 2015 — 11 yrs on file
Profile last updated
April 15, 2025
Year of graduation
2015 — 11 yrs since
Specialty taxonomy
208C00000X — NUCC code
State license (1)
Missouri #2017007784
Medicaid
MO #200044671

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1003297177. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
23
Distinct HCPCS
1
Medicare allowed
$3,720
HCPCS Description Services Patients Avg allowed
99204 New patient office or other outpatient visit, 45-59 minutes 23 23 $162

In context: peer comparison

Among 9 peers in this city , average services per provider: 28. This provider delivers 0.8× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$1,094
Transactions
2
Manufacturers
1
Payer (manufacturer) Industry Txns Amount
INTUITIVE SURGICAL, INC. 2 $1,094.20

By nature of payment

Education
$1,000
Food and Beverage
$94

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
62
Patients
57
Total drug cost
$1,086
Drug Type Claims Patients Total cost
Metronidazole Generic 21 19 $33
Neomycin Sulfate Generic 16 15 $107
Sod Sulf-Potass Sulf-Mag Sulf (Sodium, Potassium,mag Sulfates) Brand 13 11 $909
Ondansetron Odt (Ondansetron) Brand 12 12 $37

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. William Chapman's medical specialty?
Dr. William Chapman practices Colon & Rectal Surgery Physician in Saint Louis, MO.
Where does Dr. William Chapman practice?
Dr. William Chapman practices at 1044 N Mason RD, Saint Louis, MO 631416431. Office phone: 3144547177.
What is Dr. William Chapman's NPI?
Dr. William Chapman's National Provider Identifier (NPI) is 1003297177, issued by NPPES.
Does Dr. William Chapman accept Medicare assignment?
Yes. Dr. William Chapman accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. William Chapman commonly perform?
Top Medicare-reported procedures in 2023: New patient office or other outpatient visit (HCPCS 99204). Source: CMS Medicare Physician & Other Practitioners file.