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Dr. Matt Zak, M.D.

Psychiatry Physician in De Pere, WI · enumerated 2006 · practices at St Vincent Hospital-Hospital Sisters-Third Order of St Francis.

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

National Provider Identifier

1275621807

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Registry record

Entity type Individual (Type 1)
Name Dr. Matt Zak
Credential M.D.
Sex Male
Practice address 3860 Monroe Rd, De Pere, WI, 54115
Phone (920) 496-4700
Enumeration date Oct 10, 2006
Last updated in NPPES Nov 1, 2019

Taxonomy & licenses

2084P0800X Psychiatry Physician Allopathic & Osteopathic Physicians · License 50191 (MN) Secondary
2084P0800X Psychiatry Physician Allopathic & Osteopathic Physicians · License 036-113009 (IL) Secondary
2084P0800X Psychiatry Physician Allopathic & Osteopathic Physicians · License 46164-020 (WI) Primary
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
1275621807 Medicaid MN -
1575621807 Medicaid WI -

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.

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Frequently asked questions

Where does Matt Zak practice?
The practice location on file with NPPES is in De Pere, WI. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Matt Zak?
The National Provider Identifier (NPI) for Matt Zak is 1275621807, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2019-11-01.