Maria Tan, MD
Maria Tan, MD is a General Practice Physician in Missouri City, TX, registered under NPI 1689666158. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty. 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 4501 CARTWRIGHT RD STE 604, Missouri City, TX 77459. 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 |
|---|---|---|
| F3356 | TX | General Practice Physician primary |
| F3356 | TX | Family Medicine Physician |
This provider holds licence F3356 issued in TX. 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
- 5294850285
Medicare enrolment is recorded as approved under the provider type Practitioner - Family Practice. This means the provider is enrolled to bill Medicare, though it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What General Practice covers
A physician who specializes in the general practice of diagnosing, treating, and managing patients with a variety of illnesses and conditions. NUCC Health Care Provider Taxonomy, code 208D00000X
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 | |
|---|---|---|---|---|
| 208D00000X | General Practice Physician | F3356 | TX | primary |
| 207Q00000X | Family Medicine Physician | F3356 | TX |
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 | 1689666158 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Aug 19, 2005 |
| Last updated | Mar 31, 2010 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | MD |
| Practice address |
4501 CARTWRIGHT RD STE 604 Missouri City, TX 77459 (281) 499-9606 |
| Mailing address |
PO BOX 454 Missouri City, TX 77459 |
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 | 6 | 8 | 9 | 6 | 6 | 6 | 1 | 5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 6 | 7 | 9 | 3 | 6 | 3 | 1 | 1 |
Sum = 62 · next multiple of 10 = 70 · check digit = 8 · actual last digit = 8
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.