When it comes to describing outstanding payments or amounts, there are plenty of synonyms to choose from - and each one can help convey a slightly different meaning or level of urgency. Some common alternatives to "outstanding payment/amount" include "unpaid balance," "overdue funds," "past-due debt," "delinquent fees," and "outstanding dues." Other options might include "unresolved accounts," "neglected bills," or "pending invoices." By selecting the most appropriate term for the situation, you can help ensure that your communication is clear and effective, and that any outstanding debts are addressed in a timely and efficient manner.