Yield to maturity (YTM) is the total return anticipated on a bond if the bond is held until maturity. It is the internal rate of return (IRR) of an investment in a bond, assuming that all payments are made as scheduled and reinvested at the same rate. YTM takes into account the bond's market price, interest payments, and the return of the principal at maturity. It is expressed as an annual rate and is used to compare the expected returns from different bonds. YTM is also known as the redemption yield or book yield