Guillermo Reyes Martinez MD
About this NPIWhat this record shows.
NPI 1033912787 is registered to Guillermo Reyes Martinez MD, a Internal Medicine practising at 3134 N Clark St in Chicago, Illinois. Internal Medicine physicians (internists) specialise in the prevention, diagnosis, and treatment of diseases in adults, often coordinating care across multiple subspecialties. Guillermo Reyes Martinez MD has been enumerated in the National Provider Identifier (NPI) registry since 2025.
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Insurance & acceptsHow to confirm coverage.
The National Plan and Provider Enumeration System (NPPES) registry does not include commercial insurance network data, so we cannot show which plans Guillermo Reyes Martinez MD accepts. To confirm in-network status with your specific health plan, contact Guillermo Reyes Martinez MD directly at (312) 766-4949.
Frequently asked
Yes. NPI 1033912787 is registered as Active in the CMS NPPES public registry and passes the Luhn check-digit validation that all 10-digit NPIs use.
Internal Medicine physicians (internists) specialise in the prevention, diagnosis, and treatment of diseases in adults, often coordinating care across multiple subspecialties.
The CMS NPPES Public Registry at npiregistry.cms.hhs.gov is the authoritative source. FindMyNPI mirrors this dataset and refreshes monthly. For real-time verification, you can also call the provider's office at (312) 766-4949.
An individual healthcare provider has a single Type-1 NPI for life. Organisations can hold separate Type-2 NPIs per location, specialty, or sub-entity. Guillermo Reyes Martinez MD is a Type-1 individual NPI.