Can you please advise how I can cash in Series I bonds? We are purchasing a new house and we need some cash. We have approximately $30,000.00 in I bonds and we would like to cash in about $8,000.00. Can I do this on line? Tom's response If you have a Treasury Direct online account and these are electronic bonds, you can cash them online. If they are paper bonds, you need to take them to a bank with appropriate identification. Most banks can redeem them for you - it's usually easiest to do this at a bank where you have an account. Some Series I Bonds pay a lot more interest than others, so you need to be careful about which ones you select to redeem. Click here to see our chart of Series I Savings Bond rankings. The ones you redeem must be at least one year old. You will have to forego the last three months interest on any that aren't at least five years old; since I Bonds were introduced just six years ago, that will probably apply to most of your bonds. Click here to visit the premier independent web site on U.S. Savings Bonds.