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Mark J Sebastian, DMD

Dentist in Federal Way, WA · enumerated 2005.

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

National Provider Identifier

1477536027

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Registry record

Entity type Individual (Type 1)
Name Mark J Sebastian
Credential DMD
Sex Male
Practice address 33516 9th Ave S, Westhill Court Bldg 2, Federal Way, WA, 98003
Fax (253) 952-2129
Enumeration date Nov 28, 2005
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

122300000X Dentist Dental Providers · License 5374 (WA) Primary
DMD · Doctor of Medicine in Dentistry: A licensed dentist; DMD and DDS are equivalent dental degrees. About the DMD credential

Other identifiers

Identifier Type State Issuer
0040673 Other WA LABOR & INDUSTRIES

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 Mark Sebastian practice?
The practice location on file with NPPES is in Federal Way, WA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Mark Sebastian?
The National Provider Identifier (NPI) for Mark Sebastian is 1477536027, 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 2007-07-08.