Erik Sowder, PH.D.
Erik Sowder, PH.D. is a Cognitive & Behavioral Psychologist in San Francisco, CA, registered under NPI 1366770703. 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 110 GARDENSIDE DR APT 501, San Francisco, CA 94131. 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
NPPES does not list a state licence number for this record. That is not unusual — organizations and some provider types are not required to file one. Verify current licensure with the relevant state board before care.
- Status
- Approved
- Provider type
- Practitioner - Clinical Psychologist
- PAC ID
- 8729523907
- Enrollment ID
- I20240711003207
Medicare enrolment is recorded as approved under the provider type Practitioner - Clinical Psychologist. 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 Cognitive & Behavioral covers
A psychologist who reflects an experimental-clinical approach distinguished by use of principles of human learning and development and theories of cognitive processing to promote meaningful change in maladaptive human behavior and thinking. NUCC Health Care Provider Taxonomy, code 103TB0200X
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 | 1366770703 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Nov 23, 2009 |
| Last updated | Dec 8, 2025 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | PH.D. |
| Practice address |
110 GARDENSIDE DR APT 501 San Francisco, CA 94131 (707) 369-2315 |
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 | 3 | 6 | 6 | 7 | 7 | 0 | 7 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 3 | 3 | 6 | 5 | 7 | 0 | 7 | 0 |
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.