Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Leo Maxwell Cass, M.D.
Specialist in Winchester, MA · enumerated 2006.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1033158795
See something wrong? Report a correction
Registry record
Entity type Individual (Type 1)
Name Leo Maxwell Cass
Credential M.D.
Sex Male
Practice address 223 Swanton St, Winchester, MA, 01890
Phone (781) 721-5025
Fax (781) 729-2297
Enumeration date Jun 6, 2006
Last updated in NPPES Mar 17, 2018
Taxonomy & licenses
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure.
About the MD 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.
Frequently asked questions
Where does Leo Cass practice?
The practice location on file with NPPES is in Winchester, MA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Leo Cass?
The National Provider Identifier (NPI) for Leo Cass is 1033158795, a Type 1 (individual) record in the CMS NPPES registry.
Other providers at this practice address
Browse all →Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2018-03-17.