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Mark Robert Johnston, A.U.D., CCC-A

Audiologist in San Antonio, TX · enumerated 2008 · practices at Heart Medical Group, P.A..

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

National Provider Identifier

1326295726

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Registry record

Entity type Individual (Type 1)
Name Mark Robert Johnston
Credential A.U.D., CCC-A
Sex Male
Practice address 19026 Stone Oak Pkwy, Ste 110, San Antonio, TX, 78258
Phone (210) 545-0404
Fax (210) 614-1003
Enumeration date Aug 27, 2008
Last updated in NPPES Aug 27, 2008

Taxonomy & licenses

231H00000X Audiologist Speech, Language and Hearing Service Providers · License 50770 (TX) Primary
AUD · Doctor of Audiology: A licensed audiologist diagnosing and treating hearing and balance disorders. About the AUD credential

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

What is the NPI number for Mark Johnston?
The National Provider Identifier (NPI) for Mark Johnston is 1326295726, a Type 1 (individual) record in the CMS NPPES registry.
Where does Mark Johnston practice?
The practice location on file with NPPES is in San Antonio, TX. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-08-27.