- A Series I bond is a non-marketable, interest-bearing US government savings bond.
- Series I bonds provide investors with income plus inflation protection against their purchasing power and are considered low-risk investments.
- Bonds cannot be bought or sold on the secondary market.
- Series I bonds carry a fixed interest rate for the life of the bond and a variable inflation rate that is adjusted every May and November.
- These bonds have a 20-year original maturity with a 10-year extension, for a total of 30 years.