Los Ranchos is a census-designated place in San Luis Obispo County, California.

Los Ranchos is an area of residential subdivisions surrounding the San Luis Obispo Country Club.

It is located between the San Luis Obispo County Regional Airport and Edna, California.

According to the United States Census Bureau, the CDP covers an area of 2.8 square miles (7.3 km2), 99.88% of it land and 0.12% of it water.

There were 634 housing units at an average density of 223.8 per square mile (86.4/km2), of which 524 (89.9%) were owner-occupied, and 59 (10.1%) were occupied by renters.