N.D. Cent. Code § 26.1-52-04
Each insurer authorized to write and who is engaged in writing within this state, on a direct basis, basic property insurance or any component thereof in multiperil policies or homeowners insurance shall participate in the facility as a condition of its authority to do the business of insurance in this state. Members of the facility are responsible for the cost of funding the operations, expenses, and losses of the facility. Each year the board shall assess the members based upon each member's pro rata share of the aggregate property insurance premium written in the second preceding calendar year as disclosed in the annual statement and other reports filed by members with the commissioner. The assessment must be based on the premiums reported from income from this state in the following lines of the annual statement: fire, allied lines, and homeowners multiple peril.
N.D.C.C. § 26.1-52-04