when purchasing bonds it s important for the investor to understand the difference between the yield basis and the net yield basis on the secondary market you can purchase bonds through a broker dealer who could charge you a flat commission for this service however in lieu of a commission your broker may opt to sell bonds on a net yield basis 
net yield means the yield also includes the broker s profit for the transaction this is the broker s markup which is the difference between what the broker paid for the bonds and what the broker sells them for if a broker offers bonds on a net yield basis they ve already included their markup for example if an online broker sells you a bond with a 3 75 yield to maturity ytm their profit is embedded directly in the price you pay and there is no separate commission 