There are no overdue fines if you are a KU student, if you return the item.

HOWEVER

if you do not return a book withing 30 days of the Date Due, the Library will seal your student account. This means you cannot register for classes or receive an official transcript until the overdue item(s) are returned.  Once they are returned, your records are released.  You would not owe the library any fees, unless the materials were damaged in some way.