EE bond doubling calculator
A Series EE savings bond is guaranteed to be worth at least twice its purchase price at 20 years — an effective return of about 3.5% per year if held the full term. At today’s EE fixed rate of 2.40%, the fixed rate alone does not reach double in 20 years, so the Treasury makes a one-time adjustment at year 20 to get there. Enter a purchase amount below to see the compounded value, the guaranteed double, and the top-up.
Source: TreasuryDirect. Data as of May 2026.
How the doubling guarantee works
EE bonds earn a fixed rate (currently 2.40%) that is locked for the first 20 years. The bond accrues interest monthly and compounds semiannually. Separately, the Treasury guarantees the bond will be worth at least double what you paid at the 20-year mark. If 20 years of the fixed rate has not doubled the bond, the Treasury adds a one-time adjustment so the value lands at exactly 2x.
This is why EE bonds are usually a 20-year hold: cash out at year 19 and you only get the (small) fixed-rate accrual; hold to year 20 and you lock in the ~3.5% annual equivalent. After 20 years the Treasury may set a new rate; EE bonds stop earning at 30 years.
Frequently asked questions
Do EE bonds really double in 20 years?
Yes. The U.S. Treasury guarantees that a Series EE bond will be worth at least twice its purchase price at 20 years. If the fixed rate alone does not get there, Treasury makes a one-time adjustment at year 20 to reach exactly double.
What return does the 20-year double imply?
Doubling in exactly 20 years is an effective annual yield of about 3.5% (2^(1/20) - 1). At today's EE fixed rate of 2.40%, compounding alone falls well short of double in 20 years, so the guarantee's top-up is what delivers most of the return — but only if you hold the full 20 years.
What happens if I cash an EE bond before 20 years?
You only get the accrued interest at the fixed rate (and you forfeit the last 3 months of interest if you cash before 5 years). The doubling guarantee applies only at the 20-year mark, so cashing early means giving up the top-up entirely.
Related
Not investment or tax advice. BondValue is an independent reference, not affiliated with the U.S. Treasury or TreasuryDirect. Savings bond rates reset every 6 months (on May 1 and November 1), and any value shown here is an estimate. Verify current rates and the exact penny value of your bonds at TreasuryDirect’s official Savings Bond Calculator. Consult a qualified professional before making financial decisions.
Last updated: 2026-06-21