Your lender may charge a fee if you repay your mortgage early. But if your 30-year loan doesn’t have a prepayment penalty, then you can pay it off more quickly without the pressure of a 15-year loan. Even just a little here and there when you have extra cash can help chop down your principal balance and reduce the total amount of interest you’ll pay. So, be sure to ask if your mortgage has a prepayment penalty before you close.