Dr. William Cahill MD
About this NPIWhat this record shows.
NPI 1366461048 is registered to Dr. William Cahill MD, a Internal Medicine practising at 50 Lech Walesa in San Francisco, California. Internal Medicine physicians (internists) specialise in the prevention, diagnosis, and treatment of diseases in adults, often coordinating care across multiple subspecialties. Dr. William Cahill MD has been enumerated in the National Provider Identifier (NPI) registry since 2006.
Medicare enrollment
This provider holds a Medicare enrollment 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
- I20060919000544Interventional Pain ManagementCA
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 Dr. William Cahill MD accepts. To confirm in-network status with your specific health plan, contact Dr. William Cahill MD directly at (415) 554-2727.
Frequently asked
Yes. NPI 1366461048 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 (415) 554-2727.
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. Dr. William Cahill MD is a Type-1 individual NPI.