Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Donald Mesier
Counselor in Key Largo, FL · enumerated 2019.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1225675879
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Registry record
Entity type Individual (Type 1)
Name Donald Mesier
Sex Male
Practice address 99198 Overseas Hwy, Key Largo, FL, 33037
Phone (305) 434-7660
Enumeration date Dec 3, 2019
Last updated in NPPES Dec 3, 2019
Taxonomy & licenses
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 Donald Mesier practice?
The practice location on file with NPPES is in Key Largo, FL. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Donald Mesier?
The National Provider Identifier (NPI) for Donald Mesier is 1225675879, a Type 1 (individual) record in the CMS NPPES registry.
Other providers at this practice address
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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2019-12-03.