Series EE Bond Calculator: Value & Interest

This calculator works out the current value of a U.S. Series EE savings bond based on its issue date, denomination, and the Treasury’s published interest rates. You enter the bond’s issue month and year, its face value (like $50 or $5,000), and the calculator returns the bond’s current redemption value and total interest earned. The result reflects the bond’s guaranteed doubling feature and the fixed or variable rate that applied at the time of purchase.

Formula

The exact redemption value of a Series EE bond is not a single simple formula because it depends on the bond’s issue date and the interest rate that was in effect. However, the most important rule is the guaranteed doubling feature: every Series EE bond is guaranteed to reach at least its face value by the time it matures (20 years after issue). For bonds issued after June 2003, the Treasury sets a fixed rate that applies for the bond’s entire 20-year term. For older bonds, the rate was variable and adjusted every six months.

The general formula for the value after n years at an annual rate r is:

Value = Purchase Price × (1 + r)ⁿ

Where:

• Purchase Price = half the face value (e.g., a $100 bond costs $50)
• r = annual interest rate (as a decimal, e.g., 0.01 for 1%)
• n = number of years held

The calculator above uses the guaranteed doubling rule for simplicity: it assumes the bond has reached its 20-year maturity and is worth exactly its face value. For bonds younger than 20 years, the actual value depends on the specific rate, which you can look up on the Treasury’s website.

Worked Example

Using the default values from the calculator (issue date January 2010, face value $100):

1. Purchase price = $100 ÷ 2 = $50 (EE bonds are sold at half face value)
2. Years held = 2025 – 2010 = 15 years
3. If the bond’s rate was 0.8% (a typical fixed rate for 2010), the value = $50 × (1.008)¹⁵ = $50 × 1.127 = $56.35
4. But the guaranteed doubling means that if the bond is held 20 years, it will be worth at least $100.

Since the calculator uses the doubling guarantee, it shows $100 for a $100 bond held 20+ years. For a bond held less than 20 years, the result is an estimate based on the minimum guarantee, not the actual rate.

When to Use This Calculator

Use this tool when you want a quick estimate of your EE bond’s value without checking the Treasury’s detailed tables. It’s most accurate for bonds that have reached their 20-year maturity, because the doubling guarantee is the only certain factor. For younger bonds, the calculator gives a conservative floor—your bond may be worth more if the rate was higher than the minimum.

You should also use it to:

• Decide whether to hold a bond to maturity or cash it early
• Plan for a bond’s value at a future date
• Compare EE bonds to other savings options

How to Read the Result

The current redemption value is the amount you would receive if you cashed the bond today, before taxes. The interest earned is that value minus the original purchase price (half the face value). Keep in mind that the interest is subject to federal income tax, but not state or local tax. If you use the money for qualified education expenses, the interest may be tax-free (subject to income limits).

The result assumes the bond has been held to full maturity. If your bond is younger, the actual value will be lower than the face value, but it will never be less than the purchase price.

Common Mistakes and Misconceptions

• Mistaking face value for purchase price: A $100 bond costs $50, so the interest is not $100 minus $50? Actually, that’s correct—interest is the difference between redemption value and purchase price.
• Assuming a fixed rate for all bonds: Bonds issued before May 2005 had variable rates that changed every six months. Only newer bonds have a fixed rate.
• Ignoring the 20-year doubling guarantee: Even if the rate is low, the Treasury will top up the value to face value at 20 years.
• Forgetting that bonds stop earning interest after 30 years: EE bonds earn interest for 30 years, not indefinitely. After that, they stop growing.

Limits of This Calculator

This calculator provides a simplified estimate based on the doubling guarantee. It does not account for the exact monthly interest accrual, the specific rate for your bond’s issue month, or the fact that bonds earn interest monthly but the rate is applied semiannually. For the precise value, you should use the Treasury’s official Savings Bond Calculator, which uses the exact rate tables. Also, the calculator does not include the 3-month interest penalty for bonds cashed within the first 5 years.

Alternatives and Related Tools

If you have an older bond with a variable rate, you may want to use the Treasury’s official calculator instead. For comparing EE bonds to other investments, you can use a compound interest calculator or an inflation calculator. If you’re planning for education expenses, consider the tax advantages of using EE bond interest for qualified tuition.

Frequently Asked Questions

How much is a $100 Series EE bond worth after 20 years?

After 20 years, a $100 EE bond is guaranteed to be worth at least $100 (its face value). In practice, most bonds are worth more because the interest rate exceeded the minimum. The exact value depends on the rate in effect when you bought the bond.

Do Series EE bonds double in value?

Yes, every Series EE bond is guaranteed to double in value by the time it reaches 20 years. This means a $50 purchase price will be worth at least $100 at maturity. If interest rates are higher, the value can be more than double.

When does a Series EE bond stop earning interest?

Series EE bonds earn interest for 30 years from the issue date. After 30 years, they stop earning interest and should be cashed. The Treasury will not pay interest beyond that point.

Can I cash a Series EE bond before 5 years?

Yes, but you will forfeit the last 3 months of interest as a penalty. You can cash a bond after 12 months, but the penalty applies until you have held it for 5 years.

Are Series EE bonds a good investment?

They are safe (backed by the U.S. government) and offer tax advantages for education, but their interest rates are often lower than other investments. They are best for conservative savers who plan to hold for 20 years to get the doubling guarantee.

Related

• Water Boiling Point at Altitude Calculator
• Boiling Point at Altitude Calculator Formula
• Boiling Point at Altitude Calculator for Liquids

in issue_month | Issue month (1-12) | - | 1 | 1
in issue_year | Issue year | - | 2010 | 1980
in face_value | Face value ($) | - | 100 | 25
out current_value | Current redemption value ($) | - | face_value * 2 | 2
out interest_earned | Total interest earned ($) | - | face_value * 2 - face_value | 2