The U.S. Department of Treasury issues savings bonds with a unique serial number that's used to track the bond's owner and value. As of 2012, there are 14 different types of savings bonds. The most common -- several of which no longer earn interest -- are Series E, EE, H, HH, I and Savings Notes. Although it's helpful to know a bond's serial number, you don't have to have the bond in front of you to find out what it's worth. As long as you know some basic information, you can use a savings bond calculator to estimate a bond's current and future value.
Write down everything you know about the savings bond. Include the bond's denomination and approximate month and year the bond was issued.
Find the savings bond calculator on the Treasury Direct website. The calculator is located in the "Individuals" section under the "Tools" tab. Click "Get Started" at the bottom of the page display the calculator on your screen.
Select the bond type and denomination from the drop-down list. Because you don't know the serial number, leave this field blank. Enter the approximate issue date in the last field. Click "Calculate." The approximate value of the bond will display on your screen, including the original purchase price and the interest earned.
Angela M. Wheeland specializes in topics related to taxation, technology, gaming and criminal law. She has contributed to several websites and serves as the lead content editor for a construction-related website. Wheeland holds an Associate of Arts in accounting and criminal justice. She has owned and operated her own income tax-preparation business since 2006.