RLI Insurance Company writes multiple lines insurance on an admitted basis in the United States, the District of Columbia and Puerto Rico. It markets coverage to retail producers from several its casualty, surety and property operations. The company s businesses are marketed through branch offices located throughout the United States. RLI Insurance Company operates Mt. Hawley Insurance Company, which writes surplus lines insurance in the United States, the District of Columbia, the Virgin Islands and Puerto Rico. RLI Insurance Company is a part of RLI Corporation, which underwrites property and casualty insurance through its subsidiaries. It was founded in 1965.