In observe, a 40-year mortgage is a trade-off: The longer mortgage tacks on an additional decade of repayments and added curiosity. The distinction between a 30-year and 40-year mortgage on a $650,000 property may very well be as a lot as $350,000 over the course of the life cycle, $400,000 on an $800,000 property. However the longer-term mortgage additionally lowers month-to-month funds.