Mont. Code Ann. § 19-18-511

On or before April 1 annually, the clerk of every city having an organized fire department or a partly paid or volunteer department shall file with the commissioner of insurance of this state a certificate stating that fact. The certificate must include the system of water supply in use in the fire department, the number of its organized companies, steam, hand, or other engines, hook-and-ladder trucks, hose-carts, and feet of hose in actual use, and other facts that the commissioner may require.