Refine: property outside Illinois, or the proposed law
%
Illinois computes the tax as if everything were here, then keeps only the Illinois share. Which property counts as sited elsewhere is a legal question settled on the return.
Illinois estate tax
$456,071
Federal estate tax
$0
Combined
$456,0717.6% of the estate
Above the Illinois line, under the federal one: Illinois is the only estate tax in the room at this size.