The manner in which food is taxed depends upon 2 distinct factors that must both be considered in determining if food is taxed at the high rate as "food prepared for immediate consumption" or the low rate as "food prepared for consumption off the premises where sold".
1) The first factor is whether the retailer selling the food provides premises for consumption of food. If so, a rebuttable presumption is created that all sales of food by that retailer are considered to be prepared for immediate consumption and subject to tax at the high rate. As a result of this presumption, even bulk food could potentially be taxable at the high rate. However, this presumption is rebutted if a retailer demonstrates that:
A) the area for on-premises consumption is physically separated or otherwise distinguishable from the area where food not for immediate consumption is sold; and
B) the retailer has a separate means of recording and accounting for collection of receipts from sales of both high and low rate foods. For purposes of this subsection (b)(1)(B), the phrase "separate means of recording and accounting for collection of receipts" includes cash registers that separately identify high rate and low rate sales, separate cash registers, and any other methods by which the tax on high and low rate sales are recorded at the time of collection.
2) The second factor is the nature of the food item being sold. As provided in subsection (c), some foods, such as hot foods, are always considered to be "food prepared for immediate consumption", and thus subject to the high rate of tax.
3) Numerous examples applying these factors to different types of food and food retailers are provided in subsection (d)(4)(A)-(I).
See Illinois Administrative Code, Section 130.310 for more details on qualifying and non-qualifying Food, Soft Drinks and Candy.