The Washington Commonwealth Federation (WCF) was a political pressure group established in the American state of Washington in 1934 as "Commonwealth Builders, Incorporated" (CBI). The organization changed its name to Washington Commonwealth Federation in 1935. The organization did not run political candidates in its own name but rather functioned as an organized faction in the Washington State Democratic Party.
Originating out of an interest to expand the End Poverty in California movement to Washington state as a means of alleviating the misery of the Great Depression, the WCF came to be dominated by the Communist Party USA beginning in the popular front years of the late 1930s. Charged by critics to be a Communist front, the WCF was dissolved in 1948, during the era of the Second Red Scare.
The Washington Commonwealth Federation was launched in August 1934 as "Commonwealth Builders, Inc." (CBI) by a group of middle-class socialists who sought effective political action to achieve a "Cooperative Commonwealth" that included government ownership of banking and large-scale industry, state aid to farmers and small businesses, and the establishment of a network of producer and consumer cooperatives. These individuals were greatly influenced by the efforts of Upton Sinclair in his maverick End Poverty in California movement (EPIC) of 1934, marked by Sinclair's run for Governor of California behind the slogan of "production for use."