Saranap is a residential census-designated place within central Contra Costa County, California. Lying at an elevation of 180 feet, it is bounded on the south and east by portions of Walnut Creek and on the north and west by Lafayette. Saranap's ZIP code is 94595, but is addressed "Walnut Creek, CA" for delivery purposes as this is the postal designated city name used by residents. The community is in telephone area code 925. Saranap's population as of the 2010 census was 5,202.