Sarah Messmer MD
About this NPIWhat this record shows.
NPI 1073926929 is registered to Sarah Messmer MD, a Internal Medicine practising at 840 S Wood St, Room 440 Clinical Sciences North Building in Chicago, Illinois. Internal Medicine physicians (internists) specialise in the prevention, diagnosis, and treatment of diseases in adults, often coordinating care across multiple subspecialties. Sarah Messmer MD has been enumerated in the National Provider Identifier (NPI) registry since 2014.
Your brand here.
Medicare enrollment
This provider holds 2 Medicare enrollments on file with the Provider Enrollment, Chain and Ownership System (PECOS). Each enrollment carries a public Medicare Enrollment ID (ENRLMT_ID) used by billers and intermediaries.
Practitioner
- I20180905000710Internal MedicineIL
- I20250718000046Addiction MedicineIL
Source: CMS PECOS public enrollment file.
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 Sarah Messmer MD accepts. To confirm in-network status with your specific health plan, contact Sarah Messmer MD directly at (312) 996-4242.
Frequently asked
Yes. NPI 1073926929 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) 996-4242.
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. Sarah Messmer MD is a Type-1 individual NPI.