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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Gregory N Wiersema, MST-CCC/A

Audiologist in Fond Du Lac, WI · enumerated 2005.

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

National Provider Identifier

1831195361

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Registry record

Entity type Individual (Type 1)
Name Gregory N Wiersema
Credential MST-CCC/A
Sex Male
Practice address 221 Fond Du Lac Ave, Fond Du Lac, WI, 54935
Fax (920) 923-4678
Enumeration date Jun 21, 2005
Last updated in NPPES Sep 11, 2025

Taxonomy & licenses

231H00000X Audiologist Speech, Language and Hearing Service Providers · License 55-156 (WI) Primary
237600000X Audiologist-Hearing Aid Fitter Speech, Language and Hearing Service Providers · License 55-156 (WI) Secondary

Other identifiers

Identifier Type State Issuer
41105900 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.

Read the full guide → Validate an NPI →

Frequently asked questions

Is NPI 1831195361 active?
Yes, as of the latest NPPES snapshot, NPI 1831195361 is active (record last updated 2025-09-11).
How do I verify Gregory Wiersema's NPI record?
Cross-check NPI 1831195361 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-09-11.