35 ILCS 630/8
If a person who originates or receives telecommunications in this State claims to be a reseller of such telecommunications, such person shall apply to the Department for a resale number. Such applicant shall state facts which will show the Department why such applicant is not liable for tax under this Article on any of his purchases and shall furnish such additional information as the Department may reasonably require.
Upon approval of the application, the Department shall assign a resale number to the applicant and shall certify such number to him. The Department may cancel any such number which is obtained through misrepresentation, or which is used to originate or receive such telecommunications tax-free when such actions in fact are not for resale, or which no longer applies because of the person's having discontinued the making of resales.
Except as provided hereinabove in this Section, the act or privilege of originating or receiving telecommunications in this State shall not be made tax-free on the ground of being a sale for resale unless the person has an active resale number from the Department and furnishes that number to the retailer in connection with certifying to the retailer that any sale to such person is nontaxable because of being a sale for resale.
35 ILCS 630/8