Tony Chou, M.D.
Tony Chou, M.D. is a Cardiovascular Disease Physician in San Francisco, CA, registered under NPI 1457389009. This provider registers 3 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 400 PARNASSUS AVE FL 5, San Francisco, CA 94143. 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 |
|---|---|---|
| G64698 | CA | Cardiovascular Disease Physician primary |
| G64698 | CA | Internal Medicine Physician |
| G64698 | CA | Interventional Cardiology Physician |
This provider holds licence G64698 issued in CA. 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 Cardiovascular Disease covers
An internist who specializes in diseases of the heart and blood vessels and manages complex cardiac conditions such as heart attacks and life-threatening, abnormal heartbeat rhythms. NUCC Health Care Provider Taxonomy, code 207RC0000X
All registered taxonomy codes
This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 207RC0000X | Cardiovascular Disease Physician Cardiovascular Disease | G64698 | CA | primary |
| 207R00000X | Internal Medicine Physician | G64698 | CA | |
| 207RI0011X | Interventional Cardiology Physician Interventional Cardiology | G64698 | 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 | 1457389009 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jun 30, 2006 |
| Last updated | Sep 11, 2025 |
| Status | Active |
| Sole proprietor | No |
| Credential | M.D. |
| Practice address |
400 PARNASSUS AVE FL 5 San Francisco, CA 94143 (415) 353-2873 Fax (415) 353-2528 |
| Mailing address |
1635 DIVISADERO ST SUITE 625, BOX 1821 San Francisco, CA 94143 |
| Other identifiers |
00G646980
· Medicaid (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 | 5 | 7 | 3 | 8 | 9 | 0 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 4 | 1 | 7 | 6 | 8 | 9 | 0 | 0 |
Sum = 61 · next multiple of 10 = 70 · check digit = 9 · actual last digit = 9
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.