Most Series EE bonds have a total interest-paying life that extends beyond the original maturity date, up to 30 years from issuance.
The Series I bonds come with a fixed coupon rate and receive an additional inflation-adjusted interest rate that is adjusted semi-annually. Paper I bonds are no longer sold directly, but can be purchased electronically or indirectly as part of a tax refund.
Unlike Series EE bonds, I bonds do not come with a guarantee to at least double in value over the initial term of the bond. Series EE bonds are government savings bonds that have a guarantee from the US government to at least double in value over the first term of the bond.
The initial term usually lasts for 20 years, but most EE bonds have an interest-paying life that extends an additional 10 years past that term. They cannot be bought or sold in the open market, hence, they are classified as non-marketable securities.
Series EE bonds issued after May are assigned a fixed coupon rate; rates are set twice per year on May 1 and November 1, and apply to all issuances for the ensuing six months. Bonds issued after this date increase in value monthly, but interest payments are semiannual.
They are identical in every way to the paper Series EE Bonds except that any paper bonds purchased through a financial institution after December 10, have the words "Patriot Bond" printed on the top half of the bond between the Social Security Number SSN and the issue date.
Financial institutions no Ee savings bond maturity issue Series EE bonds in paper form, but the paper "Patriot Bonds" can still be cashed or converted to electronic bonds.