Mark Wallis, M.D.
Mark Wallis, M.D. is a MOHS-Micrographic Surgery Physician in Longview, TX, registered under NPI 1861489049. This provider registers 6 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 3535 N FOURTH ST STE 400, Longview, TX 75605. 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 |
|---|---|---|
| H6685 | TX | MOHS-Micrographic Surgery Physician primary |
| H6685 | TX | Dermatology Physician |
| H6685 | TX | Dermatopathology Physician |
| H6685 | TX | Clinical & Laboratory Dermatological… |
| H6685 | TX | Pediatric Dermatology Physician |
| H6685 | TX | Procedural Dermatology Physician |
This provider holds licence H6685 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 - Dermatology
- PAC ID
- 7113057563
- Enrollment ID
- I20100610000658
Medicare enrolment is recorded as approved under the provider type Practitioner - Dermatology. 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 MOHS-Micrographic Surgery covers
The highly-trained surgeons that perform Mohs Micrographic Surgery are specialists both in dermatology and pathology. With their extensive knowledge of the skin and unique pathological skills, they are able to remove only diseased tissue, preserving healthy tissue and minimizing the cosmetic impact of the surgery. Mohs surgeons who belong to the American College of Mohs Surgery (ACMS) have completed a minimum of one year of fellowship training at one of the ACMS-approved training centers in the U.S. NUCC Health Care Provider Taxonomy, code 207ND0101X
All registered taxonomy codes
This provider registers 6 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 207ND0101X | MOHS-Micrographic Surgery Physician MOHS-Micrographic Surgery | H6685 | TX | primary |
| 207N00000X | Dermatology Physician | H6685 | TX | |
| 207ND0900X | Dermatopathology Physician Dermatopathology | H6685 | TX | |
| 207NI0002X | Clinical & Laboratory Dermatological Immunology Physician Clinical & Laboratory Dermatological Immunology | H6685 | TX | |
| 207NP0225X | Pediatric Dermatology Physician Pediatric Dermatology | H6685 | TX | |
| 207NS0135X | Procedural Dermatology Physician Procedural Dermatology | H6685 | 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 | 1861489049 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Oct 3, 2005 |
| Last updated | Mar 7, 2023 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | M.D. |
| Practice address |
3535 N FOURTH ST STE 400 Longview, TX 75605 (903) 757-3881 Fax (903) 757-5948 |
| Other identifiers |
30076724
· Other (TX) 45D0684764 · Other (TX) CID037095 · Other (TX) H6685 · Other (TX) 04813881913 · Other (TX) 0898678-03 · Medicaid (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 | 8 | 6 | 1 | 4 | 8 | 9 | 0 | 4 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 8 | 3 | 1 | 8 | 8 | 9 | 0 | 8 |
Sum = 71 · next multiple of 10 = 80 · 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.