If (when) you're an employee, the following wage payment law applies in Illinois:
An employer must pay employees all wages due at least twice per month. Wages of executive, administrative and professional employees, as defined in theFair Labor Standards Act (FLSA), may be paid once a month. Commission may be paid once a month. An employee employed by an employment or labor placement agency which makes daily wage payments to employees may request in writing that their wages be paid either weekly or twice per month. Employment and labor placement agencies that make daily wage payments must provide written notice to all daily wage payment employees of the right to request weekly or semi-monthly checks. The employer may provide this notice by conspicuously posting the notice at the location where the wages are received by the daily wage employees. 820 ILCS 115/3 An employer who pays wages twice per month must pay its employees within 13 days of the end of the pay period. An employer who pays wages once per week must pay employees within 7 days of the end of the pay period. An employer who pays wages on a daily basis must pay employees on the same day the wages are earned, insofar as possible, but no later than 24 hours after the day on which the wages were earned. An employer paying executive, administrative and professional employees monthly must pay wages with 21 calendar days after the end of the pay period.
An employer must pay any employee who is absent at the time fixed for payment, or who for any other reason is not paid at that time, within a period of 5 days after the time fixed for payment. If the wages are not paid within 5 days, the employer must pay the employee within 5 days after the employee demands payment. Payment to the absent employee
shall be made by mail if the employee so requests in writing. 820 ILCS 115/4
An employee can file a wage claim/complaint with the Il. DOL - army judge gave a link. (This post is a follow up to my post above.)