Puede llenar un formulario IL-W-4 nuevo para actualizar los montos de su exención y aumentar su retención de Illinois. Complete this worksheet to figure your total withholding allowances.Everyone must complete Part 1. Illinois Secure Choice will provide a simple form for employees to use to change their contribution elections or opt out of the program. Retención de Impuestos. The Illinois Unemployment Insurance Act provides for the payment of benefits to eligible unemployed workers and for the collection of employer. The four chapters in this part provide basic information on the tax system. They take you through the first steps of filling out a tax return. Employer: Please fill out employee information below and provide employee with this document to take to any pharmacy with prescriptions.