Stephen Ostwald, D.D.S.
Stephen Ostwald, D.D.S. is a provider specialising in General Practice Dentistry in San Francisco, CA, registered under NPI 1952421653. 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 1635 DIVISADERO ST SUITE 500, San Francisco, CA 94115. 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 |
|---|---|---|
| 30245 | CA | General Practice Dentistry primary |
This provider holds licence 30245 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
- Order And Referring Only - Dentist
- PAC ID
- 0244520252
- Enrollment ID
- I20160606002457
Medicare enrolment is recorded as approved under the provider type Order And Referring Only - Dentist. 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 General Practice covers
A general dentist is the primary dental care provider for patients of all ages. The general dentist is responsible for the diagnosis, treatment, management and overall coordination of services related to patients' oral health needs. NUCC Health Care Provider Taxonomy, code 1223G0001X
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 | 1952421653 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Mar 29, 2007 |
| Last updated | May 11, 2009 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | D.D.S. |
| Practice address |
1635 DIVISADERO ST SUITE 500 San Francisco, CA 94115 (415) 775-3368 Fax (415) 775-3680 |
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 | 9 | 5 | 2 | 4 | 2 | 1 | 6 | 5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 9 | 1 | 2 | 8 | 2 | 2 | 6 | 1 |
Sum = 57 · next multiple of 10 = 60 · check digit = 3 · actual last digit = 3
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.