The cheapest auto insurance quotes in California can vary depending on the driver's specific circumstances and insurance needs. However, some companies consistently offer competitive rates. According to various sources, Geico offers the cheapest full coverage car insurance quotes in California at $124 per month, which is $31 per month cheaper than the statewide average. The Auto Club of Southern California also offers affordable rates, with an average annual rate of $1,147 for full coverage. Other companies that consistently offer cheap car insurance in California include USAA, Wawanesa, Infinity, Progressive, and GEICO. It's important for drivers to shop around and compare quotes from multiple companies to find the best deal for their specific situation.