When something is expected to be completed or delivered it is due at that time. If it is completed or delivered after the expected time it is overdue, or late. "My tax payment was due on the 15th of the month, but since today is the 20th of the month, my payment is overdue." Was this answer helpful?

The main difference between due and overdue is timing. Due implies that something must be accomplished or completed by a predetermined time, whereas overdue means that it has exceeded the expected timeframe. overdue is a debt that has not been repaid by the agreed-upon due date.

You can use "due" to describe things that are supposed to be ready/submitted/etc in the future, present, or even the past. But it can only be overdue if it was due in the past, and still hasn't been submitted/completed.

This is the correct form, used as an adjective to describe something that is past its due date or deadline. Use "overdue" as a single word to describe something that is late or past its due date. For example, "The library books are overdue." The payment is overdue.