the Ill schedule M deduction for US interest included in dividend income comes from the entry on the 1099-DIV.
a direct entry on schedule M will cause an error that may prevent e-filing even the Federal return. there is no line on the standard 1099-div where US interest is reported so importing the 1099-div info may not bring in this item. for Illinois the subtraction is entered when you get to the illinois return. it wiould ve ubnnder the income section and then items handled differently for illinois. not sure of online because in desktop that line for entry does not appear
[MODS} in desktop step-by-step, for illinois 1040 the line for subtraction of US interest on schedule M does not appear. it can be entered directly on the 1099- in form mode.
