Marin County California is covered by a total of 42 ZIP Codes. There are 2 ZIP Codes in Marin County that extend into adjacent counties ( and Sonoma County). Of the ZIP codes within or partially within Marin County there are 21 Standard ZIP Codes, 1 Unique ZIP Codes and 20 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 Marin County and can be turned on and off. Each type of postal code can also be turned on and off.