If one decides to cash in some bonds, is it better to cash in the most recent ones having earned little interest or the older ones even if the older ones are less than five years old? Tom's response I haven't mentioned it here before, but I have a new book on Savings Bonds that gives Alert Recommendations on which bonds to keep and which to cash. Click here for more info on the world's newest and bestest book on savings bonds. If your bonds are Series I, cash in the ones with the lowest fixed-base rate. If they are Series EE and they are all less than five years old, they all earn the same rate of interest. In this case, cash in the newest ones first. The strategy here is to get as many past the five-year mark as you can before you redeem them. That will avoid the three-month interest penalty for redeeming them before they're five years old.