Ill. Admin. Code tit. 56, § 300.610
The Department shall apply any gratuitous payments made by an employer to an employee upon separation against any final compensation which the employer is obligated to pay. As used herein, a gratuitous payment is money given by an employer to an employee that does not arise out of a contract or agreement between the parties or an employment policy.
(Source: Added at 16 Ill. Reg. 13828, effective September 1, 1992)