How to Find the Interest Rate on a Bond. When you buy a bond, you are actually lending your money to the government or the corporation that originally sold the bond. Bonds usually pay good interest rates compared to money market accounts or even certificates of deposit, and the interest is guaranteed until the time the bond must be paid off Bond Prices and Interest Rates A bond is an IOU. That is, a bond is a promise to pay, in the future, fixed amounts that are stated on the bond. The interest rate that a bond actually pays therefore depends on how these payments compare to the price that is paid for the bond.1 That price is determined in a To calculate the interest payment on a bond, look at the bond’s face value and the coupon rate, or interest rate, at the time it was issued. The coupon rate may also be called the face, nominal, or contractual interest rate. Multiply the bond’s face value by the coupon interest rate to get the annual interest …