Loan to value and down payments

Upon making a mortgage loan for purchase of a property, lenders usually require that the borrower make a down payment, that is, contribute a portion of the cost of the property. This down payment may be expressed as a portion of the value of the property. The loan to value ratio (or LTV) is the size of the loan against the value of the property. Therefore, a mortgage loan where the purchaser has made a down payment of 20% has a loan to value ratio of 80%. For loans made against properties that the borrower already owns, the loan to value ratio will be imputed against the estimated value of the property.
The loan to value ratio is considered an important indicator of the riskiness of a mortgage loan: the higher the LTV, the higher the risk that the value of the property (in case of foreclosure) will be insufficient to cover the remaining principal of the loan.