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SYDNEY CASTLE
NPI 1477439594
Social Worker in Seattle, WA

Active since August 13, 2025
901 BOREN AVE STE 900, SEATTLE, WA 98104(206) 257-3199 Get Directions Write a Review

NPPES record last updated: September 5, 2025. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Sep 5, 2025, Aug 13, 2025 (2 updates tracked since 2025).

About Sydney Castle NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

SYDNEY CASTLE (NPI 1477439594) is an individual social worker in Seattle, Washington, licensed in Washington (61674183) and active in the NPI registry since August 2025.

NPPES Registry Identity

NPI1477439594
Entity TypeIndividualFemale
Primary Taxonomy104100000X
Provider Legal NameSYDNEY CASTLE
Location Address901 BOREN AVE STE 900Seattle, WA 98104-3596
Mailing Address22809 Lakeview Dr Apt E302Mountlake Terrace, WA 98043-2880
Phone(206) 257-3199
Sole ProprietorNo
Enumeration DateAugust 13, 2025
Last NPPES UpdateSeptember 5, 20252 updates tracked since enumeration
NPPES CertifiedSeptember 5, 2025
✔ NPI 1477439594 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtySocial WorkerBehavioral Health & Social Service Providers
Taxonomy Code104100000X
License✔ Licensed in WA · 61674183
Definition
A social worker is a person who is qualified by a Social Work degree, and licensed, certified or registered by the state as a social worker to practice within the scope of that license. A social worker provides assistance and counseling to clients and their families who are dealing with social, emotional and environmental problems. Social work services may be rendered to individuals, families, groups, and the public.
901 BOREN AVE STE 900, Seattle, WA 98104
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Other Providers at the Same Location NPPES 2

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

CHARLOTTE MCINTOSH LSWAIC
Social Worker
901 BOREN AVE STE 900
SEATTLE, WA 98104
King County (425) 326-5300
SARA QUACH LSWAIC
Social Worker (Clinical)
901 BOREN AVE STE 900
SEATTLE, WA 98104
King County (206) 902-3402

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Sydney Castle's NPI number?

The NPI number for Sydney Castle is 1477439594. It was assigned to this individual provider in the NPPES registry on August 13, 2025.

Where is Sydney Castle located?

Sydney Castle practices at 901 Boren Ave Ste 900, Seattle, WA 98104. The listed phone number is (206) 257-3199.

What is Sydney Castle's specialty?

The primary specialty registered for this NPI is Social Worker with taxonomy code 104100000X.

When was this NPI record last updated?

The NPPES record for Sydney Castle was last updated on September 5, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.