The Market Price of a bond is determined by traders who buy and sell bonds. On any given day, your bond will be worth more or less than the face value. That’s because the bond market is continually active, with traders bidding up and down the value of bonds based on the current interest rate of the day. When interest rates rise, bonds are worth less (because it takes a smaller amount of capital to earn the same amount of interest). When interest rates fall, bonds are worth more (because it takes a greater amount of money to earn the same amount of interest.)