Business: Mercury General is the leading independent broker and agency writer of automobile insurance in California and has been one of the fastest growing automobile insurers in the nation. They are ranked as the fourth largest private passenger automobile insurer in California. Mercury also writes automobile insurance in Arizona, Florida, Georgia, Illinois, Michigan, Nevada, New Jersey, New York, Oklahoma, Pennsylvania, Texas and Virginia. In addition to automobile insurance, Mercury writes other lines of insurance in various states, including mechanical breakdown and homeowners insurance.