38 Ill. Adm. Code 110.105
Delinquency or Default Charges
Section 110.105 Delinquency
or Default Charges
a) Delinquency charges may be assessed and collected and added to
the balance of the note, but interest shall not be collected on charge.
b) Earned, but uncollected delinquency charges shall be recorded
on the account record on the date the delinquent payment is received, if the
licensee intends to collect the charges at a later date.
c) A licensee shall not directly or indirectly, to levy or
collect any delinquency charge on a payment, which payment is otherwise a full
payment for the applicable period and is paid on its due date or within an
applicable grace period when the only delinquency is attributable to late fees
or delinquency charges assessed on earlier installments.