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Dr. Mark Stuart Simmons, MD

Internal Medicine Physician in Tuscon, AZ · enumerated 2006.

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

National Provider Identifier

1811092760

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Registry record

Entity type Individual (Type 1)
Name Dr. Mark Stuart Simmons
Credential MD
Sex Male
Practice address 3870 W. River Rd, #126, Tuscon, AZ, 85741
Phone (520) 219-6616
Fax (970) 266-3660
Enumeration date Sep 14, 2006
Last updated in NPPES Sep 26, 2024

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 37923 (CO) Primary
208000000X Pediatrics Physician Allopathic & Osteopathic Physicians · License 37923 (CO) Secondary
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
81353871 Medicaid CO -
110198245 Other CO RR MEDICARE PIN

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

How do I verify Mark Simmons's NPI record?
Cross-check NPI 1811092760 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1811092760 active?
Yes, as of the latest NPPES snapshot, NPI 1811092760 is active (record last updated 2024-09-26).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2024-09-26.