How long do I have to file an appeal to an overpayment determination? July 21, 2021 16:49 Updated The appeal must be filed within thirty days from the date the overpayment determination was mailed. Related articles How do I file an appeal to an overpayment determination? What can I expect after I file my appeal? What if I do not agree with the decision? What will happen during the hearing? Why did I receive an Overpayment Determination?