Santa Ynez is a census-designated place in the Santa Ynez Valley of Santa Barbara County, California.The town of Santa Ynez is one of the communities of the Santa Ynez Valley. It features the Santa Ynez Airport for general aviation, with a paved 2804 x 75 foot runway. The population was 4,418 at the 2010 census, down from 4,584 at the 2000 census. It is named after Saint Agnes, Santa Ynez in the Spanish language.