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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. Katherine Elizabeth Gaston Mattax, ND

Naturopath in Seattle, WA · enumerated 2022 · practices at Rak Family Medicine Pllc.

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

National Provider Identifier

1053023846

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Registry record

Entity type Individual (Type 1)
Name Dr. Katherine Elizabeth Gaston Mattax
Credential ND
Sex Female
Practice address Seattle, WA, 98107
Phone (206) 279-6390
Enumeration date Dec 23, 2022
Last updated in NPPES Nov 2, 2023

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

175F00000X Naturopath Other Service Providers Primary

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 Katherine Mattax?
The National Provider Identifier (NPI) for Katherine Mattax is 1053023846, a Type 1 (individual) record in the CMS NPPES registry.
Where does Katherine Mattax practice?
The practice location on file with NPPES is in Seattle, WA. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2023-11-02.