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Mark A Mason, MD

Emergency Medicine Physician in Kirkwood, MO · enumerated 2006.

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

National Provider Identifier

1134167091

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Registry record

Entity type Individual (Type 1)
Name Mark A Mason
Credential MD
Sex Male
Practice address 525 Couch Ave, Kirkwood, MO, 63122
Phone (314) 966-1500
Fax (314) 966-1681
Enumeration date Jun 3, 2006
Last updated in NPPES Sep 26, 2014

Taxonomy & licenses

207P00000X Emergency Medicine Physician Allopathic & Osteopathic Physicians · License 102434 (MO) 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
209985902 Medicaid MO -

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.

Read the full guide → Validate an NPI →

Frequently asked questions

Is NPI 1134167091 active?
Yes, as of the latest NPPES snapshot, NPI 1134167091 is active (record last updated 2014-09-26).
How do I verify Mark Mason's NPI record?
Cross-check NPI 1134167091 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 2014-09-26.