I Bond (Series I Savings Bond): What It Is and Why It Matters
Definition
A Series I Savings Bond, or I Bond, is a type of U.S. government savings bond designed to protect your money from losing value due to inflation. It earns interest through a combination of a fixed rate and a variable rate that is adjusted twice a year based on inflation.
How It Works
An I Bond is a debt security issued by the U.S. Department of the Treasury. When you buy an I Bond, you are essentially lending money to the federal government. In return, the government pays you interest. I Bonds are sold at face value, meaning a $100 bond costs $100 to purchase.
The interest rate on an I Bond, also known as the composite rate, is made up of two components:
- A fixed rate: This rate is set when the bond is issued and remains the same for the entire 30-year life of the bond.
- A variable inflation rate: This rate is based on changes in the Consumer Price Index for all Urban Consumers (CPI-U) and is adjusted every six months, in May and November.
The composite rate is calculated using a formula that combines the fixed rate and the semiannual inflation rate. This combined rate is announced on the first business day of May and November and applies to all I Bonds for the following six months. Interest is earned monthly and compounds semiannually, meaning that every six months, the interest earned is added to the bond's principal value, and future interest is then earned on this new, higher principal.
You can purchase electronic I Bonds online through the U.S. Treasury's website, TreasuryDirect. As of January 1, 2025, paper I bonds are no longer available for purchase.
Key Rules and Limits
- Annual Purchase Limit: In 2026, you can purchase up to $10,000 in electronic I Bonds per person, per calendar year.
- Minimum Purchase: The minimum purchase for an electronic I Bond is $25.
- Holding Period: You must hold an I Bond for at least one year before you can redeem it.
- Early Redemption Penalty: If you redeem an I Bond within the first five years of owning it, you will forfeit the last three months of interest.
- Maturity: I Bonds earn interest for up to 30 years.
- Taxation: The interest earned on I Bonds is subject to federal income tax but is exempt from state and local income taxes. You can choose to report the interest income annually or defer paying taxes on the interest until you cash in the bond or it matures.
- Higher Education Tax Exclusion: You may be able to exclude the interest from federal income tax if you use the bond proceeds to pay for qualified higher education expenses for yourself, your spouse, or your dependents. Income limitations and other rules apply.
Example
Let's say in January 2026, you purchase a $1,000 I Bond with a composite rate of 4.03%. This rate is made up of a 0.90% fixed rate and a semiannual inflation rate that contributes to the overall composite rate.
For the first six months you own the bond, it will earn interest at an annualized rate of 4.03%. After six months, the interest earned will be added to your bond's principal. At that point, a new composite rate will be announced based on the latest inflation figures, and your bond will begin earning interest at that new rate for the next six months.
If you decide to cash in the bond after 18 months, you will receive your original $1,000 investment plus 15 months of accrued interest. You would forfeit the last three months of interest because you redeemed the bond before holding it for five years.
Pros and Cons
Pros
- Inflation Protection: The primary benefit of I Bonds is their ability to protect your savings from being eroded by inflation.
- Safety: I Bonds are backed by the full faith and credit of the U.S. government, making them a very safe investment.
- Tax Advantages: The interest earned is exempt from state and local taxes, and federal taxes can be deferred.
- Principal Protection: The value of your I Bond will never decline below what you paid for it.
Cons
- Purchase Limits: The annual purchase limit of $10,000 per person may be too low for some investors.
- Liquidity: You cannot redeem an I Bond for the first year, and there is a penalty for early withdrawal within the first five years.
- Variable Returns: The interest rate changes every six months, so your future returns are not guaranteed.
- Online Purchase Only: I Bonds can only be purchased electronically through the TreasuryDirect website, which some may find inconvenient.
Common Mistakes to Avoid
- Forgetting the Early Redemption Penalty: Cashing in an I Bond before five years have passed will result in a loss of the last three months of interest.
- Not Understanding the Interest Rate: The composite rate is not a guaranteed long-term return. The inflation-adjusted portion of the rate will change every six months.
- Misunderstanding the Tax Implications: While there are tax advantages, the interest is still subject to federal income tax. It's important to plan for this tax liability, especially if you are deferring it until redemption.
- Losing Track of Your Bonds: Since I Bonds are held electronically in a TreasuryDirect account, it's important to keep your account information secure and accessible.
Frequently Asked Questions
Q: How do I buy I Bonds?
A: You can purchase electronic I Bonds through the U.S. Treasury's official website, TreasuryDirect.gov. You will need to create an account, provide your personal information, and link a bank account to fund your purchases.
Q: What is the current interest rate for I Bonds?
A: The composite rate for I Bonds issued from November 2025 through April 2026 is 4.03%. This rate is a combination of a 0.90% fixed rate and a variable inflation rate. The inflation component of the rate will be recalculated in May 2026.
Q: Can I lose money with an I Bond?
A: No, you cannot lose your initial investment. The redemption value of an I Bond will not decline, and the interest rate will never fall below zero.
This article reflects 2026 rules and limits. Tax laws and financial regulations change — consult a qualified financial advisor or visit IRS.gov for the latest information.