There are 3 US Post Offices in Zavala County serving a total of 11,690 residents equating to 3,897 residents per post office. It's estimated that approximately 18,659 packages are handled across the 3 county post offices annually. Zavala County is a county located in the U.S. state of Texas. As of the 2010 census, the population was 11,677. Its county seat is Crystal City. The county was created in 1858 and later organized in 1884. Zavala is named for Lorenzo de Zavala, Mexican politician, signer of the Texas Declaration of Independence, and first vice president of the Republic of Texas."