Zackery Williams
Zackery Williams is a provider specialising in Contractor in Milwaukee, WI, registered under NPI 1801689195. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 1435 N 50TH ST, Milwaukee, WI 53208. 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 |
|---|---|---|
| W4529948300307 | WI | Contractor primary |
This provider holds licence W4529948300307 issued in WI. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.
What Contractor covers
For the purposes of the Health Care Provider Taxonomy, a contractor is limited to individuals who do construction or mechanical work to modify a patient's environment to accommodate a health condition. Contractors perform projects including, but not limited to, building wheelchair ramps, widening doorways, modifying personal vehicles, and making other improvements for patient access and movement. This code has no relation to a provider's employment status. NUCC Health Care Provider Taxonomy, code 171W00000X
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 | 1801689195 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | May 28, 2025 |
| Last updated | May 28, 2025 |
| Status | Active |
| Sole proprietor | Yes |
| Practice address |
1435 N 50TH ST Milwaukee, WI 53208 (407) 451-7201 |
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 | 8 | 0 | 1 | 6 | 8 | 9 | 1 | 9 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 8 | 0 | 1 | 3 | 8 | 9 | 1 | 9 |
Sum = 65 · next multiple of 10 = 70 · check digit = 5 · actual last digit = 5
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.