William Chapman, MD
William Chapman, MD is a Colon & Rectal Surgery Physician in Saint Louis, MO, registered under NPI 1003297177. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 1044 N MASON RD DIV SURG COLON/RECTAL, STE 310, Saint Louis, MO 63141. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 2017007784 | MO | Surgery Physician |
| 2017007784 | MO | Colon & Rectal Surgery Physician primary |
This provider holds licence 2017007784 issued in MO. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Colorectal Surgery (proctology)
- PAC ID
- 3274847876
- Enrollment ID
- I20230606000999
Medicare enrolment is recorded as approved under the provider type Practitioner - Colorectal Surgery (proctology). Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Colon & Rectal Surgery covers
A colon and rectal surgeon is trained to diagnose and treat various diseases of the intestinal tract, colon, rectum, anal canal and perianal area by medical and surgical means. This specialist also deals with other organs and tissues (such as the liver, urinary and female reproductive system) involved with primary intestinal disease. NUCC Health Care Provider Taxonomy, code 208C00000X
All registered taxonomy codes
This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 208600000X | Surgery Physician | 2017007784 | MO | |
| 208C00000X | Colon & Rectal Surgery Physician | 2017007784 | MO | primary |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1003297177 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jun 15, 2015 |
| Last updated | Apr 15, 2025 |
| Status | Active |
| Sole proprietor | No |
| Gender | Male |
| Credential | MD |
| Practice address |
1044 N MASON RD DIV SURG COLON/RECTAL, STE 310 Saint Louis, MO 63141 (314) 454-7177 Fax (888) 425-7946 |
| Mailing address |
PO BOX 7412011 Chicago, IL 60674 |
| Other identifiers |
200044671
· Medicaid (MO) |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 0 | 0 | 3 | 2 | 9 | 7 | 1 | 7 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 4 | 9 | 5 | 1 | 5 |
Sum = 53 · next multiple of 10 = 60 · check digit = 7 · actual last digit = 7
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.