The antonyms for "settled up" are primarily related to unfinished business or unsettled debts. Some of these antonyms include "owing," "unpaid," "outstanding," "unsettled," "debtor," "indebted," and "unreconciled." These words imply that there is still an obligation that needs to be fulfilled, either in terms of money or unfinished tasks. For example, if you have not paid your bills, then your accounts are still "unpaid" or "outstanding." Alternatively, if you're in the middle of a dispute, then it can be said that the matter is "unsettled" or "unresolved." In conclusion, antonyms for "settled up" indicate there is still some work to be done to fully resolve the situation.