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Mastery Mental Health Pllc

Clinical Social Worker in Mukilteo, WA · enumerated 2020 · authorized official Geoffrey Simkins, Owner/Counselor.

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

National Provider Identifier

1356942064

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Registry record

Entity type Organization (Type 2)
Legal business name Mastery Mental Health Pllc
Practice address 627 5th St Ste 200, Mukilteo, WA, 98275
Phone (206) 309-3839
Fax (425) 513-2329
Enumeration date Nov 9, 2020
Last updated in NPPES Nov 9, 2020

Taxonomy & classification

101Y00000X Counselor Behavioral Health & Social Service Providers Secondary
1041C0700X Clinical Social Worker Behavioral Health & Social Service Providers Primary

Authorized official

Name Geoffrey Simkins
Title Owner/Counselor
Phone (360) 566-3722

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 a Type 2 NPI?
A Type 2 NPI identifies an organization (group practice, hospital, pharmacy, lab), while Type 1 NPIs identify individual providers. Organizations bill under their Type 2 NPI.
What type of organization is Mastery Mental Health Pllc?
Mastery Mental Health Pllc is registered in NPPES as a Clinical Social Worker (its primary provider taxonomy).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2020-11-09.