A California Petition For Probate is filed in the Superior Court in the county where the decedent lived at the time of death. For example, if the decedent lived in Riverside County, but the real estate they owned was located in San Bernardino County, the probate case would be filed in the Riverside County. A common mistake is trying to file in the county where the property is located, rather than where the decedent lived, if it’s not the same. If they were not a California resident, but left property in California, the probate would be filed in the county where the real estate is located.  The same is true if you are filing a California Spousal Property Petition or a California Petition to Determine Succession to Real Property.