You can contact the Administration Office in several ways:

Phone or Fax:

Phone: (844) 811-6789
Fax: (206) 505-9727



Email for Eligibility for Health & Welfare Coverage and Updating Your Personal Information or Records.


Email for questions regarding health contributions, remittance forms and reciprocity.

Website or Technical Questions

Email for website question such as questions about your account or website access.


NW Insulation Workers Welfare Trust
PO Box 34203
Seattle, WA 98124-1203

In Person:

The Administration Office (Washington) is open from 8:00-5:00 pm, Monday to Friday.

7525 SE 24th Street, Suite 200
Mercer Island, WA 98040