Contra Costa County California is covered by a total of 57 ZIP Codes. There are 7 ZIP Codes in Contra Costa County that extend into adjacent counties ( and Alameda County). Of the ZIP codes within or partially within Contra Costa County there are 42 Standard ZIP Codes, 1 Unique ZIP Codes and 13 PO Box ZIP Codes.
Click on the ZIP Codes in the interactive map to view more information. The map control in the upper right corner can be used to toggle map layers on and off. The red outline is the border of Contra Costa County and can be turned on and off. Each type of postal code can also be turned on and off.