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Drs. Larson, Martyn, & Hafner, LLP

General Practice Dentistry in Mequon, WI · enumerated 2007 · authorized official David Martyn, Dentist Partner.

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

National Provider Identifier

1588700900

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Registry record

Entity type Organization (Type 2)
Legal business name Drs. Larson, Martyn, & Hafner, LLP
Practice address 10562 N Port Washington Rd, Mequon, WI, 53092
Phone (262) 240-1220
Fax (262) 240-1232
Enumeration date Jan 30, 2007
Last updated in NPPES Mar 26, 2008

Taxonomy & classification

1223G0001X General Practice Dentistry Dental Providers Primary

Authorized official

Name David Martyn
Title Dentist Partner
Phone (262) 240-0554

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

What is the NPI number for Drs. Larson, Martyn, & Hafner, LLP?
The NPI for Drs. Larson, Martyn, & Hafner, LLP is 1588700900, a Type 2 (organization) record in the CMS NPPES registry.
Who is the authorized official for Drs. Larson, Martyn, & Hafner, LLP?
NPPES lists David Martyn (Dentist Partner) as the authorized official for this organization.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-03-26.