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John William Duff, MD

Family Medicine Physician in Midland, MI · enumerated 2006.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1225125222

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Registry record

Entity type Individual (Type 1)
Name John William Duff
Credential MD
Sex Male
Practice address 2213 Dilloway Dr, Midland, MI, 48640
Phone (989) 493-3882
Enumeration date Oct 10, 2006
Last updated in NPPES Apr 18, 2011

Taxonomy & licenses

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License JD088515 (MI) Primary
207P00000X Emergency Medicine Physician Allopathic & Osteopathic Physicians · License 4301088515 (MI) Secondary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
4301088515 Other MI STATE LICENSE

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.

Read the full guide → Validate an NPI →

Frequently asked questions

What is the NPI number for John Duff?
The National Provider Identifier (NPI) for John Duff is 1225125222, a Type 1 (individual) record in the CMS NPPES registry.
Where does John Duff practice?
The practice location on file with NPPES is in Midland, MI. Providers can have multiple locations; NPPES lists the primary practice address.

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-04-18.