Points on a mortgage, also called discount points or mortgage points, let you buy down your interest rate. One point usually costs 1 percent of the loan amount, paid at closing, and lowers your mortgage rate by about 0.25 percent. So for example, if NBKC offered you a 4.5 percent mortgage rate on a $250,000 loan, you might be able to buy a point for $2,500 and lower your rate to 4.25 percent.