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Series I Bond


A Series I Bond is a type of U.S. Treasury savings bond designed to protect investors from inflation while providing a fixed interest rate. These bonds are issued by the U.S. government and are adjusted for inflation every six months, using the Consumer Price Index for All Urban Consumers (CPI-U). Series I Bonds offer low risk, semi-annual compounding interest, and tax-deferred growth, making them a popular long-term savings option.


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Key Takeaways

  1. Series I Bonds are government-issued, low-risk, inflation-protected securities designed to protect your investment against inflation while providing a moderate return.
  2. Interest on Series I Bonds is a combination of a fixed rate and an inflation-adjusted rate, ensuring that your investment keeps up with inflation and maintains its purchasing power over time.
  3. You can purchase Series I Bonds electronically through the US Department of Treasury’s website (TreasuryDirect), and they can be redeemed after holding them for at least one year, with minimal penalties for redemptions made within the first five years.


The Series I Bond is an important financial instrument in business and finance due to its unique features that combine both a fixed rate of return and inflation protection. By linking its interest rates to the rate of inflation, Series I Bonds provide a safeguard against the eroding effects of inflation on an investor’s purchasing power. This makes them an ideal investment option for long-term savings, financing financial goals such as retirement, higher education, or other life milestones. Additionally, as a low-risk, government-backed security issued by the U.S. Department of the Treasury, these bonds guarantee the return of initial investment principal and provide tax-deferred interest, further enhancing their appeal to investors seeking stability and long-term growth.


Series I Bonds serve as an accessible investment tool for individuals to hedge against inflation and protect the purchasing power of their savings. These government-backed debt securities, issued by the U.S. Department of the Treasury, are designed to adapt alongside fluctuations in the economy, adjusting their interest rates in accordance with the Consumer Price Index for All Urban Consumers (CPI-U). As such, they provide a safe, low-risk investment option for those seeking a long-term strategy to preserve the real value of their capital without being eroded by inflation over time. The purpose of Series I Bonds extends beyond merely being an instrument to combat inflation for the typical investor. They contribute towards financing the federal budget deficit, which plays a critical role in the United States’ economic stability. Furthermore, Series I Bonds offer valuable benefits, such as being tax-deferred until redemption or reaching maturity (30 years), exempt from state and local taxes, and offering flexible redemption options after 12 months. These unique characteristics make Series I Bonds an appealing choice for investors seeking a dependable, low-maintenance addition to their financial portfolio, as well as for those who are risk-averse and prioritize the preservation of their hard-earned savings.


Series I Bonds are a type of government-backed savings bond issued by the U.S. Department of the Treasury designed to protect against inflation while encouraging long-term investment. Here are three real-world examples that illustrate various aspects of Series I Bonds: 1. Retirement Savings: A person in their 40s decides to diversify their retirement savings and protect their investments from inflation. They decide to purchase Series I Bonds with a portion of their savings, which offer a fixed interest rate and an additional inflation-adjusted interest rate. Over the years, their investment adjusts to keep up with inflation, ensuring their retirement savings maintain their purchasing power. 2. Education Savings: A newly married couple starts planning for their future family and the potential cost of college for their future children. They choose to invest in Series I Bonds as part of their college savings strategy because of their tax advantages for education purposes. As long as the money from the redeemed bonds is used for qualified education expenses, the interest earned is federal tax-free, helping the family reach their savings goals while minimizing tax liability. 3. Emergency Fund: An individual decides to create an emergency savings fund to provide a financial safety net in case of unexpected expenses (such as job loss, medical expenses, or home repairs). They allocate a portion of their emergency fund to Series I Bonds to provide a safe, low-risk investment that will not only maintain, but grow in value due to the inflation-adjustment and interest provided by this type of government bond.

Frequently Asked Questions(FAQ)

What is a Series I Bond?
A Series I Bond is a type of non-marketable, interest-bearing U.S. government savings bond designed to protect investors from inflation and to provide a secure, low-risk investment option.
How do Series I Bonds work?
Series I Bonds earn interest by combining a fixed rate and an inflation rate, adjusted every six months. The interest is accrued and compounded semiannually, and the bond continues to earn interest for up to 30 years.
Where can I purchase Series I Bonds?
Series I Bonds can be purchased online through TreasuryDirect, a website managed by the U.S. Department of the Treasury, or through the payroll deduction program offered by some employers.
What is the minimum and maximum investment amount for Series I Bonds?
The minimum purchase for a Series I Bond is $25, while the maximum annual purchase per Social Security Number is $10,000 for electronic bonds and $5,000 for paper bonds purchased with IRS tax refunds.
Can I redeem my Series I Bonds before they mature?
Yes, you can redeem your Series I Bonds any time after holding them for 12 months. However, if you redeem them before five years, you will lose the last three months of interest.
Are Series I Bonds taxable?
The interest earned on Series I Bonds is exempt from state and local income taxes, but it is subject to federal income tax. You can choose to pay federal taxes annually or defer them until the bond is redeemed or reaches final maturity.
Can I transfer or gift Series I Bonds to another person?
Yes, you can transfer or gift electronic Series I Bonds to another person through your TreasuryDirect account.
Are Series I Bonds a good investment option?
Series I Bonds offer a low-risk investment option with guaranteed returns and protection against inflation, making them suitable for conservative investors or as a part of a diversified portfolio. However, they may not provide the highest potential returns when compared to other investment options.

Related Finance Terms

  • Inflation-Adjusted Principal
  • Composite Rate
  • Fixed Interest Rate
  • Semiannual Inflation Rate
  • TreasuryDirect

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