Series I Bond Value Calculator US Treasury

Series I Bond Value Formula:

\[ V = P \times \left(1 + \frac{\text{fixed} + 2 \times \text{inflation} + \text{fixed} \times \text{inflation}}{2}\right)^{2 \times y} \]

Purchase Amount (P):

USD

Fixed Annual Rate:

decimal

Semiannual Inflation Rate:

decimal

Years Held (y):

years

Current Value (V):

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1. What is the Series I Bond Value Calculator?

The Series I Bond Value Calculator estimates the current value of US Treasury Series I savings bonds based on the official Treasury calculation method. It accounts for both fixed and inflation-adjusted components of the bond's return.

2. How Does the Calculator Work?

The calculator uses the Series I Bond value formula:

\[ V = P \times \left(1 + \frac{\text{fixed} + 2 \times \text{inflation} + \text{fixed} \times \text{inflation}}{2}\right)^{2 \times y} \]

Where:

$ V $ — Current value of the bond (USD)
$ P $ — Purchase amount (USD)
$ \text{fixed} $ — Fixed annual rate (decimal)
$ \text{inflation} $ — Semiannual inflation rate (decimal)
$ y $ — Years held (years)

Explanation: The formula combines the fixed rate with twice the semiannual inflation rate and their interaction term, compounded semiannually over the holding period.

3. Importance of Series I Bond Valuation

Details: Accurate valuation helps investors track the performance of their inflation-protected savings bonds, plan for future expenses, and make informed investment decisions.

4. Using the Calculator

Tips: Enter the original purchase amount, the fixed rate announced at purchase, the current semiannual inflation rate, and the number of years held. All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What are Series I Bonds?
A: Series I Bonds are US government savings bonds that earn interest based on both a fixed rate and an inflation rate that adjusts semiannually.

Q2: Where can I find current rates?
A: Current fixed and inflation rates are published on the TreasuryDirect.gov website and updated every six months.

Q3: Are there any restrictions on Series I Bonds?
A: Yes, they must be held for at least one year, and if redeemed within five years, you lose the last three months of interest.

Q4: How often do inflation rates change?
A: Inflation rates are adjusted every six months (May and November) based on the Consumer Price Index.

Q5: Is there a maximum purchase amount?
A: Yes, the annual purchase limit is $10,000 per Social Security Number for electronic bonds, plus $5,000 in paper bonds via tax refund.