Here are the top 10 insurance firms in the US based on total assets, according to the National Association of Insurance Commissioners:UnitedHealth Group: With total assets of $305.4 billion, UnitedHealth Group is the largest health insurance company in the US.Berkshire Hathaway: Berkshire Hathaway is a conglomerate that owns several insurance companies, including GEICO and General Re. Its total assets amount to $788.4 billion.MetLife: With total assets of $654.6 billion, MetLife is one of the largest life insurance companies in the world.Prudential Financial: Prudential Financial is a diversified financial services company that offers life insurance, annuities, and investment products. Its total assets amount to $896.6 billion.AIG (American International Group): AIG is a global insurance company that provides property and casualty insurance, life insurance, and retirement products. Its total assets amount to $498.3 billion.New York Life Insurance: New York Life Insurance is the largest mutual life insurance company in the US, with total assets of $325.3 billion.Anthem: Anthem is a health insurance company that operates in several states across the US. Its total assets amount to $91.2 billion.Hartford Financial Services Group: Hartford Financial Services Group provides property and casualty insurance, as well as life insurance and investment products. Its total assets amount to $73.8 billion.Chubb: Chubb is a global insurance company that provides commercial and personal property and casualty insurance, as well as accident and health insurance. Its total assets amount to $174.3 billion.Allstate: Allstate is one of the largest personal lines insurance companies in the US, providing auto, home, and other insurance products. Its total assets amount to $130.9 billion.