Members of the International Association of Machinists and Aerospace Workers (IAM) District 751 in Puget Sound, District W-24 in Portland, OR and District 70 in Wichita, KS voted by 51% to 49% to accept an eight-year contract extension that includes a two-part $15,000 signing bonus and assures the 777X will be built in Puget Sound by IAM members. In addition to securing manufacture of the 777X fuselage and carbon-fiber wings for the Puget Sound, the agreement reaffirms Boeing's commitment to maintain 737 MAX production in Renton, WA through 2024. Analysts estimate the two programs could account for as many as 20,000 direct and indirect jobs and billions in economic activity.

The proposal by Boeing also includes changes to IAM members' defined benefit pension plan. While the plan will continue to pay full benefits to all members vested in the plan, Boeing will cease making contributions and members will instead be covered by a company-funded 401(k) plan and a separate savings plan that includes matching company contributions.