Michael Blair, D.O.
Michael Blair, D.O. is an Otolaryngology/Facial Plastic Surgery Physician in San Marcos, TX, registered under NPI 1104037100. 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 1340 WONDER WORLD DR STE 4031, San Marcos, TX 78666. 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 |
|---|---|---|
| P0551 | TX | Otolaryngology/Facial Plastic Surgery… primary |
This provider holds licence P0551 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 - Otolaryngology
- PAC ID
- 7113191479
Medicare enrolment is recorded as approved under the provider type Practitioner - Otolaryngology. 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 Otolaryngology/Facial Plastic Surgery covers
An otolaryngologist who specializes in the diagnosis and surgical treatment of head and neck conditions. NUCC Health Care Provider Taxonomy, code 207YX0905X
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 | 1104037100 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | May 24, 2007 |
| Last updated | May 12, 2025 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | D.O. |
| Practice address |
1340 WONDER WORLD DR STE 4031 San Marcos, TX 78666 (512) 353-6400 |
| Other identifiers |
P00995618
· RR MEDICARE (TX) 287444801 (TX) TXB140444 · MEDICARE (TX) |
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 | 1 | 0 | 4 | 0 | 3 | 7 | 1 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 1 | 0 | 4 | 0 | 3 | 5 | 1 | 0 |
Sum = 40 · next multiple of 10 = 40 · check digit = 0 · actual last digit = 0
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.