35 ILCS 120/5f
In addition to any other remedy provided for by the laws of this State, if the tax imposed by this Act is not paid within the time required by this Act, the Department, or some person designated by it, may cause a demand to be made on the taxpayer for the payment of the tax. If the tax remains unpaid for 10 days after demand has been made and no proceedings have been taken for review, the Department may issue a warrant directed to the sheriff of any county of the State or to any State officer authorized to serve process, commanding the sheriff or other officer to levy upon property and rights to property (whether real or personal, tangible or intangible) of the taxpayer, without exemption, found within his or her jurisdiction, for the payment of the amount of unpaid tax with the added penalties, interest and the cost of executing the warrant. The term "levy" includes the power of distraint and seizure by any means. In any case in which the warrant to levy has been issued, the sheriff or other person to whom the warrant was directed may seize and sell such property or rights to property. Such warrant shall be returned to the Department together with the money collected by virtue of the warrant within the time specified in the warrant, which may not be less than 20 nor more than 90 days from the date of the warrant. The sheriff or other officer to whom such warrant is directed shall proceed in the same manner as is prescribed by law for proceeding against property to enforce judgments which are entered by a circuit court of this State, and is entitled to the same fees for his or her services in executing the warrant, to be collected in the same manner. The Department, or some officer, employee or agent designated by it, may bid for and purchase any such property sold.
No proceedings for a levy under this Section may be commenced more than 20 years after the latest date for filing of the notice of lien under Section 5b of this Act, without regard to whether such notice was actually filed.
Any officer or employee of the Department designated in writing by the Director is authorized to serve process under this Section to levy upon accounts or other intangible assets of a taxpayer held by a financial organization, as defined by Section 1501 of the Illinois Income Tax Act. In addition to any other provisions of this Section, any officer or employee of the Department designated in writing by the Director may levy upon the following property and rights to property belonging to a taxpayer: contractual payments, accounts and notes receivable and other evidences of debt, and interest on bonds, by serving a notice of levy on the person making such payment. Levy shall not be made until the Department has caused a demand to be made on the taxpayer in the manner provided above. In addition to any other provisions of this Section, any officer or employee of the Department designated in writing by the Director, may levy upon the salary, wages, commissions and bonuses of any employee, including officers, employees, or elected officials of the United States as authorized by Section 5520a of the Government Organization and Employees Act (5 U.S.C. 5520a), but not upon the salary or wages of officers, employees, or elected officials of any state other than this State, by serving a notice of levy on the employer. Levy shall not be made until the Department has caused a demand to be made on the employee in the manner provided above. The provisions of Section 12-803 of the Code of Civil Procedure relating to maximum compensation subject to collection under wage deduction orders shall apply to all levies made upon compensation under this Section. To the extent of the amount due on the levy, the employer or other person making payments to the taxpayer shall hold any non-exempt wages or other payments due or which subsequently come due. The levy or balance due thereon is a lien on wages or other payments due at the time of the service of the notice of levy, and such lien shall continue as to subsequent earnings and other payments until the total amount due upon the levy is paid, except that such lien on subsequent earnings or other payments shall terminate sooner if the employment relationship is terminated or if the notice of levy is rescinded or modified. The employer or other person making payments to the taxpayer shall file, on or before the return dates stated in the notice of levy (which shall not be more often than bimonthly) a written answer under oath to interrogatories, setting forth the amount due as wages or other payments to the taxpayer for the payment periods ending immediately prior to the appropriate return date. A lien obtained hereunder shall have priority over any subsequent lien obtained pursuant to Section 12-808 of the Code of Civil Procedure, except that liens for the support of a spouse or dependent children shall have priority over all liens obtained hereunder.
In any case where property or rights to property have been seized by an officer of the Illinois Department of Law Enforcement, or successor agency thereto, under the authority of a warrant to levy issued by the Department of Revenue, the Department of Revenue may take possession of and may sell such property or rights to property and the Department of Revenue may contract with third persons to conduct sales of such property or rights to the property. In the conduct of such sales, the Department of Revenue shall proceed in the same manner as is prescribed by law for proceeding against property to enforce judgments which are entered by a circuit court of this State. If, in the Department's opinion, no offer to purchase at such sale is acceptable and the State's interest would be better served by retaining the property for sale at a later date, then the Department may decline to accept any bid and may retain the property for sale at a later date.
35 ILCS 120/5f