The difference in the yield between different issues of securities. There is a yield spread between the U.S. TreasuryÂ’s 2-year notes and the 30-year bond. Yield spread also exists between corporate and Treasury debt. For instance, the yield spread between a 10-year corporate bond and the 10-year Treasury note could be 75 basis points. This means that the corporate bond pays 0.75 percent more than the Treasury note.