toolbox
Home / Money & Investing / Treasury Ladder After Tax Value Estimator

Treasury Ladder After Tax Value Estimator

The Treasury Ladder After Tax Value Estimator projects the ending value of a Treasury ladder after federal income tax on annual interest. Under current U.S. rules, interest on marketable Treasury bills, notes, and bonds is subject to federal income tax but exempt from state and local income taxes.

The calculator uses an average annual yield and assumes tax on modeled interest is paid each year before the remaining interest is reinvested. It can help compare a Treasury ladder with fully taxable fixed-income alternatives, but it does not price individual securities or account for capital gains, losses, premiums, discounts, or inflation.

Inputs

USD
%
years
%
Result
—
Estimated after-tax ending value
Gross ending value—
Estimated federal tax paid—
After-tax gain—

1. Enter starting principal
Use the amount allocated to the Treasury ladder.

2. Enter an average yield
Use a planning yield that represents the ladder across the selected period.

3. Choose the holding period
Enter the number of years over which after-tax compounding is modeled.

4. Enter federal marginal rate
Treasury interest is federally taxable, so use the marginal rate you want applied to modeled annual interest.

5. Review gross versus after-tax value
The difference shows the estimated federal tax drag under the annual-tax assumption.

After-tax annual rate = y × (1 − f)
After-tax ending value = Principal × (1 + after-tax annual rate)^Years

y is the average annual Treasury yield and f is the federal marginal income-tax rate. The model does not apply state or local income tax to Treasury interest.

For comparison, gross ending value compounds at the pre-tax yield. Annual taxes are approximated from the difference in each year’s gross interest and retained interest.

What the result means

The main result estimates principal plus retained, reinvested Treasury interest after the modeled federal tax drag.

Treasury tax reporting and return calculations can differ by security type, purchase price, and account type; this is a planning estimate.

Given: $200,000 starting principal, 4.25% annual yield, 7 years, and a 24% federal marginal tax rate.

Calculation: After-tax annual rate = 4.25% × (1 − 0.24) = 3.23%. Ending value = $200,000 × 1.03237 ≈ $249,845.

Result: Estimated after-tax ending value of about $249,845.

Interpretation: The model retains the principal and compounds interest after federal tax, with no state or local income tax applied to Treasury interest.

Why is there no state income-tax input?

Interest on marketable U.S. Treasury securities is exempt from state and local income taxes under current U.S. rules. The calculator therefore applies only the federal rate to modeled Treasury interest.

Does the result include Treasury price changes?

No. It assumes a stable principal base and reinvested interest. Selling before maturity can create gains or losses that are outside this model.

Can I use a Treasury bill yield in this calculator?

Yes as an annualized planning yield, but bills are issued at a discount and their actual cash-flow timing differs from coupon-paying notes and bonds.

What if I hold Treasuries in a retirement account?

The current-tax model may not apply because tax timing depends on the account. Evaluate the account’s distribution rules separately.

Is the federal rate the same as my effective tax rate?

Not necessarily. The calculator uses a user-entered marginal rate as a simplifying assumption, not a full tax-return calculation.