Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. John Edward Mason, M.D.

Surgery Physician in Chesterfield, MO · enumerated 2005.

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

National Provider Identifier

1275528580

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Registry record

Entity type Individual (Type 1)

Name Dr. John Edward Mason

Credential M.D.

Sex Male

Practice address 226 S Woods Mill Rd, Suite 49 W, Chesterfield, MO, 63017

Phone (314) 434-1211

Fax (314) 434-4419

Enumeration date Sep 13, 2005

Last updated in NPPES Feb 26, 2018

Taxonomy & licenses

208600000X Surgery Physician Allopathic & Osteopathic Physicians · License 104004 (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
205802101	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.

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Frequently asked questions

How do I verify John Mason's NPI record?

Cross-check NPI 1275528580 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

Is NPI 1275528580 active?

Yes, as of the latest NPPES snapshot, NPI 1275528580 is active (record last updated 2018-02-26).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2018-02-26.