Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

William Cornwell III

Individual provider Mental Health Counselor · NPI 1164730842

William Cornwell III is a Mental Health Counselor in Seattle, Washington. Practices as a sole proprietor. Registered with an NPI since 2010.

In the registry since
2010

Practice location Address checks out

1812 E Madison St
Seattle, WA 98122-2843
Phone: (425) 610-9403
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Mental Health Counselor (primary) Taxonomy 101YM0800X

Record details

NPI number1164730842
Entity typeIndividual (Type 1)
GenderMale
Sole proprietorYes
NPI enumeratedSeptember 16, 2010
Last updated in NPPESSeptember 16, 2010
Mailing address433 31st Ave E, Upper Level, Seattle, WA 98112-4826

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