Shell Ridge is a census-designated place[2] in Contra Costa County, California, United States.

The 2010 United States census reported Shell Ridge's population was 959.

According to the United States Census Bureau, the CDP has a total area of 0.430 square miles (1.11 km2), all of it land.

Shell Ridge first appeared as a census designated place in the 2010 U.S.

There were 370 housing units at an average density of 860.6 per square mile (332.3/km2),of which 357 were occupied, 334 (93.6%) by the owners and 23 (6.4%) by renters.