Unified Western Grocers is a retailer-owned wholesale grocery cooperative that supplies independent supermarkets in the Western United States. It was formed in 1999 as the merger of United Grocers of Oregon (founded 1915) and Certified Grocers of California (founded 1922). In 2007 it acquired Associated Grocers of Seattle, Washington and changed their name to Unified Grocers.
Unified Grocers is currently the largest retailer-owned wholesaler in the western United States. They serve more than 3,000 retail stores and recorded annual sales over $3billion in 2007. There are over 500 current members and growing.