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Dr. Leon Samuel Greos, MD

Allergy & Immunology Physician in Centennial, CO · enumerated 2006 · practices at Colorado Allergy and Asthma Centers, PC.

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

National Provider Identifier

1003887738

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Registry record

Entity type Individual (Type 1)
Name Dr. Leon Samuel Greos
Credential MD
Sex Male
Practice address 13111 E Briarwood Ave Ste 340, Centennial, CO, 80112
Phone (303) 632-3694
Fax (303) 632-3692
Enumeration date Jan 31, 2006
Last updated in NPPES May 4, 2021

Taxonomy & licenses

207K00000X Allergy & Immunology Physician Allopathic & Osteopathic Physicians · License DR.0028923 (CO) 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
01289230 Medicaid CO -

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 Leon Greos?
The National Provider Identifier (NPI) for Leon Greos is 1003887738, a Type 1 (individual) record in the CMS NPPES registry.
Where does Leon Greos practice?
The practice location on file with NPPES is in Centennial, CO. 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 2021-05-04.