The term 'in ARREARS' (owing) is used to describe a situation in which someone has not paid a debt or bill by the due date. It is usually used to refer to a situation in which a person or organization has failed to make a payment on time and is now obligated to pay the amount owed, plus any additional fees or interest that may have accrued. In some cases, the person or organization may be required to pay a penalty for being in ARREARS.