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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. Mark S Wallis, M.D.

MOHS-Micrographic Surgery Physician in Longview, TX · enumerated 2005 · practices at Wallis Dermatology Associates Pllc.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1861489049

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Registry record

Entity type Individual (Type 1)
Name Dr. Mark S Wallis
Credential M.D.
Sex Male
Practice address Longview, TX, 75605
Phone (903) 757-3881
Fax (903) 757-5948
Enumeration date Oct 3, 2005
Last updated in NPPES Mar 7, 2023

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

207N00000X Dermatology Physician Allopathic & Osteopathic Physicians · License H6685 (TX) Secondary
207ND0900X Dermatopathology Physician Allopathic & Osteopathic Physicians · License H6685 (TX) Secondary
207NI0002X Clinical & Laboratory Dermatological Immunology Physician Allopathic & Osteopathic Physicians · License H6685 (TX) Secondary
207NP0225X Pediatric Dermatology Physician Allopathic & Osteopathic Physicians · License H6685 (TX) Secondary
207NS0135X Procedural Dermatology Physician Allopathic & Osteopathic Physicians · License H6685 (TX) Secondary
207ND0101X MOHS-Micrographic Surgery Physician Allopathic & Osteopathic Physicians · License H6685 (TX) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
30076724 Other TX DPS NUMBER
45D0684764 Other TX CLIA NUMBER
CID037095 Other TX CIDC NUMBER
H6685 Other TX MEDICAL LICENSE NUMBER
04813881913 Other TX MED. ED. NUMBER
0898678-03 Medicaid TX -

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

Is NPI 1861489049 active?
Yes, as of the latest NPPES snapshot, NPI 1861489049 is active (record last updated 2023-03-07).
How do I verify Mark Wallis's NPI record?
Cross-check NPI 1861489049 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2023-03-07.