The percentage of the value of the property for which a mortgage is required. This ratio is important in determining whether or not default insurance is required, and if so, what the cost of that insurance will be (see \"Mortgage InsuranceM\") For example, if the property value is $200,000, the down payment available is $20,000 and the required mortgage is $180,000. The LTV is $180,000/$200,000 or 90%.