20 ILCS 2505/2505-640

(a) The Department may enter into agreements with any other state for the reciprocal collection by the Department pursuant to the Reciprocal Tax Collection Act of taxes owed to that state and collection by the other state pursuant to a provision of its law similar to the Reciprocal Tax Collection Act of taxes owed to this State. (b) An agreement under this Section shall contain provisions relating to: (1) safeguards against the disclosure or inappropriate use of any information that identifies, directly or indirectly, a particular taxpayer obtained or maintained pursuant to the agreement, or that is required to be kept confidential under the applicable laws of either state or of the United States; and (2) a minimum threshold for the amount of taxes owed by a taxpayer to a state that would trigger the operation of the agreement.