Your Illinois income includes the adjusted gross income (AGI) amount figured on your federal return, plus any additional income that must be added to your AGI. Some of your income may be subtracted when figuring your Illinois base income. For more information, see the IL-1040 Step-by-Step Instructions.
Yes, income from unemployment is subject to tax in Illinois.
Questions regarding inheritance tax should be directed to the Office of the Attorney General at 217 524-5095.