William Chow, D.O.
William Chow, D.O. is a Specialist in Oakland, CA, registered under NPI 1417981192. 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 3120 WEBSTER ST, Oakland, CA 94609. 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 |
|---|---|---|
| 20A4862 | CA | Specialist primary |
This provider holds licence 20A4862 issued in CA. 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 - Micrographic Dermatologic Surgery (mds)
- PAC ID
- 8022057710
Enrolled in Medicare 6 times, across 5 states:
| State | Enrollment ID | Provider type |
|---|---|---|
| California | I20050502001223 | Practitioner - Micrographic Dermatologic Surgery (mds) |
| South Carolina | I20210716000310 | Practitioner - Dermatology |
| Georgia | I20210910001280 | Practitioner - Micrographic Dermatologic Surgery (mds) |
| Florida | I20220204001105 | Practitioner - Dermatology |
| Alabama | I20220316001375 | Practitioner - Dermatology |
| Georgia | I20231207002273 | Practitioner - Dermatology |
Medicare enrolment is recorded as approved under the provider type Practitioner - Micrographic Dermatologic Surgery (mds). There are 6 separate enrolment records across 5 states (CA, SC, GA, FL, AL). Multiple enrolments usually mean the provider bills Medicare from more than one practice location, or has kept an earlier enrolment after moving. Each record carries its own enrolment ID, listed above. 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 Specialist covers
An individual educated and trained in an applied knowledge discipline used in the performance of work at a level requiring knowledge and skills beyond or apart from that provided by a general education or liberal arts degree. NUCC Health Care Provider Taxonomy, code 174400000X
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 | 1417981192 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jul 10, 2006 |
| Last updated | Jul 21, 2021 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | D.O. |
| Practice address |
3120 WEBSTER ST Oakland, CA 94609 (510) 681-8587 Fax (888) 939-4229 |
| Mailing address |
501 BEALE ST PH 1B San Francisco, CA 94105 |
| Other identifiers |
20A4862
· Other (CA) |
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 | 4 | 1 | 7 | 9 | 8 | 1 | 1 | 9 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 4 | 2 | 7 | 9 | 8 | 2 | 1 | 9 |
Sum = 68 · next multiple of 10 = 70 · check digit = 2 · actual last digit = 2
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.