How to calculate the fair value of a bond? A bond that is near to the interest payment date (coupon date) would likely be pricier. But how much is fair? Any formula? Suggestions? I work in a financial company and some people sell/buy previously issued government bonds (from Central American countries) before maturity (i.e. secondary market) and they ask me for a opinion on price. This bonds are quite safe, in the last 20+ years this governments have never defaulted. Thanks a lot for your help