Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Dr. Marshall Diamond, DMD
Dentist in Commack, NY · enumerated 2007.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1689894651
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Registry record
Entity type Individual (Type 1)
Name Dr. Marshall Diamond
Credential DMD
Sex Male
Practice address 777 Larkfield Road, Commack, NY, 11725
Phone (631) 462-5780
Enumeration date May 1, 2007
Last updated in NPPES Jul 8, 2007
Taxonomy & licenses
DMD · Doctor of Medicine in Dentistry: A licensed dentist; DMD and DDS are equivalent dental degrees.
About the DMD 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 Marshall Diamond practice?
The practice location on file with NPPES is in Commack, NY. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Marshall Diamond?
The National Provider Identifier (NPI) for Marshall Diamond is 1689894651, a Type 1 (individual) record in the CMS NPPES registry.
Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.