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Mark M. Theiss, MD, P.C.

Orthopaedic Surgery Physician in Fairfax, VA · enumerated 2009 · authorized official Audrey Carr, Office Manager.

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

National Provider Identifier

1770716656

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Registry record

Entity type Organization (Type 2)
Legal business name Mark M. Theiss, MD, P.C.
Practice address 8316 Arlington Blvd, Suite 414, Fairfax, VA, 22031
Phone (703) 573-2218
Fax (703) 573-2373
Enumeration date Aug 26, 2009
Last updated in NPPES Aug 26, 2009

Taxonomy & classification

207X00000X Orthopaedic Surgery Physician Allopathic & Osteopathic Physicians · License 0101036798 (VA) Primary

Authorized official

Name Audrey Carr
Title Office Manager
Phone (703) 573-2218

Other identifiers

Identifier Type State Issuer
TH475892 Medicaid VA -

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

Where is Mark M. Theiss, MD, P.C. located?
The practice location on file with NPPES is in Fairfax, VA.
How current is this record?
Data comes from the CMS NPPES public dissemination file; this record was last updated in NPPES on 2009-08-26. Verify at npiregistry.cms.hhs.gov.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2009-08-26.