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Dr. Andrew Mel Diaz, DO

Internal Medicine Physician in Huntley, IL · enumerated 2020 · practices at Questcare Obstetrics of Illinois, LLC.

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

National Provider Identifier

1255951786

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Registry record

Entity type Individual (Type 1)
Name Dr. Andrew Mel Diaz
Credential DO
Sex Male
Practice address 10400 Haligus Rd, Huntley, IL, 60142
Phone (815) 759-4323
Fax (815) 759-4948
Enumeration date Apr 24, 2020
Last updated in NPPES Apr 16, 2026

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 036164669 (IL) Primary
DO · Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD. About the DO credential

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 Andrew Diaz?
The National Provider Identifier (NPI) for Andrew Diaz is 1255951786, a Type 1 (individual) record in the CMS NPPES registry.
Where does Andrew Diaz practice?
The practice location on file with NPPES is in Huntley, IL. Providers can have multiple locations; NPPES lists the primary practice address.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2026-04-16.