There are 16 US Post Offices in Yolo County serving a total of 236,025 residents equating to 14,752 residents per post office. It's estimated that approximately 376,722 packages are handled across the 16 county post offices annually. Yolo County, officially the County of Yolo, is a county located in the northern portion of the U.S. state of California. As of the 2010 census, the population was 200,849. Its county seat is Woodland. Yolo County is included in the Sacramento-Roseville-Arden-Arcade, CA Metropolitan Statistical Area. The county is located in the Sacramento Valley, Much of Yolo County remains a relatively rural agricultural region. This is evidenced by the multibillion-dollar state of California tomato industry that accounts for 90% of the canned and processed tomato production in the United States and 35% worldwide, to which Yolo County is a major contributor."