William Welsh, D.O.
William Welsh, D.O. is a Geriatric Medicine (Internal Medicine) Physician in Whittier, CA, registered under NPI 1568401255. 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 7624 PAINTER AVE #100, Whittier, CA 90602. 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 |
|---|---|---|
| 20A4272 | CA | Geriatric Medicine (Internal Medicine)… primary |
| 20A4272 | CA | Family Medicine Physician |
This provider holds licence 20A4272 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 - Family Practice
- PAC ID
- 8022084912
- Enrollment ID
- I20090812000647
Medicare enrolment is recorded as approved under the provider type Practitioner - Family Practice. 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 Geriatric Medicine covers
An internist who has special knowledge of the aging process and special skills in the diagnostic, therapeutic, preventive and rehabilitative aspects of illness in the elderly. This specialist cares for geriatric patients in the patient's home, the office, long-term care settings such as nursing homes and the hospital. NUCC Health Care Provider Taxonomy, code 207RG0300X
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 | |
|---|---|---|---|---|
| 207RG0300X | Geriatric Medicine (Internal Medicine) Physician Geriatric Medicine | 20A4272 | CA | primary |
| 207Q00000X | Family Medicine Physician | 20A4272 | CA |
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 | 1568401255 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jun 6, 2006 |
| Last updated | Sep 1, 2009 |
| Status | Active |
| Sole proprietor | No |
| Credential | D.O. |
| Practice address |
7624 PAINTER AVE #100 Whittier, CA 90602 (562) 945-9333 Fax (562) 945-8533 |
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 | 5 | 6 | 8 | 4 | 0 | 1 | 2 | 5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 5 | 3 | 8 | 8 | 0 | 2 | 2 | 1 |
Sum = 55 · next multiple of 10 = 60 · 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.