Occurs when the borrower fails to make a payment as they are required. Late fees may not be charged, but even if it is a little late, it will be considered to be late and the loan delinquent. Typically speaking, if a payment has not been made within 30 days of the date it was due, the loan is considered to be in default. Some lending institutions do not have a 30 day rule and can theoretically take your home as soon as it is 1 day late, although many try to avoid this if possible. It is a terrible mark to have against your credit.