The county was originally to be called Mt. Diablo County, but the name was changed prior to incorporation as a county. The county's Spanish language name means opposite coast, because of its location opposite San Francisco, in an easterly direction, on San Francisco Bay.
Owing to its extensive waterfront on the San Francisco, San Pablo, and Suisun bays, the county's north-western and northern segments have long been sites for heavy industry, including a number of still active oil refineries and chemical plants.
Yes, Contra Costa, CA offers a great blend of suburban charm, urban convenience, and a high quality of life that makes it a great place to live, particularly if you enjoy a family-friendly or peaceful atmosphere.
The minimum combined 2025 sales tax rate for Contra Costa County, California is 8.75%. This is the total of state, county, and city sales tax rates.
If you are: a person (this includes sole-proprietors) you may claim up to $12,500; if you are a Corporation, limited liability company or partnership, you may claim up to $6,250.
Contra Costa County is known for its diverse communities, thriving economy, and abundant recreational opportunities.
About. In 2022, Contra Costa County, CA had a population of 1.16M people with a median age of 40.1 and a median household income of $120,020.
Where to file by City, ZIP code CityZIP Code(s)Your courthouse is Hilltop Mall 94806 George D. Carroll Courthouse, Richmond Knightsen 94548 Richard E. Arnason Justice Center, Pittsburg Lafayette 94549 Wakefield Taylor Courthouse, Martinez Martinez 94553 Wakefield Taylor Courthouse, Martinez32 more rows