Amends GS 150B-19 to prohibit an agency from adopting a rule that results in additional costs for those subject to the rule unless the rule must be adopted in order to respond to: (1) a serious and unforeseen threat to public health, safety, or welfare; (2) an act of the General Assembly or Congress; (3) a change in federal or state budgetary policy; (4) a federal regulation; or (5) a court order. Applies to rules adopted on or after the act’s effective date.