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Do Business With Us

Do Business With Us


Tips for Success

View the Upcoming Capital Projects to learn more about anticipated contracting opportunities. 

We advertise in the Seattle Times. Or, register as a vendor to sign up for automatic email notifications

If you are invited by NAICS code to participate in a publicly advertised solicitation, you will automatically receive notice when addenda are issued.

If you were not invited to participate in the solicitation, you can view details of all advertised solicitations on the Solicitations Abstract webpage.

You must register in the E-Procurement Supplier Portal in order to access solicitations. Once registered you must login to "View Active Solicitations" from the homepage to search the solicitation you’re interested in. You must "Acknowledge Participation" in order to create a response and see addenda.

King County uses rosters for projects less than $500,000.

Roster projects are unadvertised; only roster members are invited to submit proposals for roster projects. Because of their limited scope, roster projects are ideal for small firms.

Visit the Rosters page for more information.

You can attend a pre-proposal meeting for advertised contracts to network with prime consultants. 

You can also visit our Solicitation Resources page to view lists of document holders and pre-proposal meeting attendees to find other businesses interested in a solicitation. 

Visit the SCS Directory to search by category, NAICS, CSI, name or description.

Firms interested in current or upcoming work that believe there may be a potential conflict of interest because of previous or concurrent work with King County (or any other related third-party work) may seek a written determination from King County regarding the firm's eligibility to propose. King County's written response will be binding. Written requests must include the following information:

  1. A detailed description of the specific scope of the previous or concurrent work and how it relates to the specific scope of work to be performed by the firm for upcoming work;
  2. The identification of any personnel that will be used on the current scope of work that also were involved in the previous or concurrent work and their respective roles on each;
  3. A detailed explanation regarding why the firm believes there is no conflict of interest that would preclude the firm from performing the scope of work; and
  4. Any internal measures that the firm proposes to implement to eliminate any potential or perceived conflict of interest that would preclude the firm from performing the work.

Subconsultants to potential prime proposers may seek similar determinations, but the required information must be submitted to King County through a potential prime consultant.


Submit written requests to:
Regina Sparano, Architecture & Engineering Services Team Lead

A/E Roster

Roster projects are not advertised; only roster members can bid. 

King County uses rosters for smaller projects (less than $500,000). 

Apply for roster membership

Contact Us

Phone: 206-263-9400

TTY Relay: 711

Fax: 206-296-7676