Are Treasuries always better than CDs in high-tax states?

Not necessarily. While Treasuries benefit from state tax exemption, a CD with a substantially higher nominal yield can still come out ahead after tax. This calculator quantifies the trade-off for your specific yields and tax rates.

Which tax rates should I use in the calculator?

Use your marginal federal and state income tax rates on ordinary income. If you are unsure, you can approximate them from current tax tables or ask a tax professional, then run a few scenarios to see how sensitive the result is to your exact bracket.

Does this calculator handle municipal bonds or other tax-free securities?

No. Municipal bonds and other tax-exempt securities have different federal and state tax rules, including potential AMT considerations. This tool is focused specifically on Treasuries versus taxable CDs.

What if I hold Treasuries or CDs in an IRA, 401(k), or HSA?

In tax-advantaged accounts, interest is not taxed annually at your marginal rates; instead, taxation generally occurs on withdrawal (or not at all in some HSA/ROTH scenarios). In that context, you would compare gross yields and other factors like liquidity and credit risk rather than after-tax yield in the current year.

Does the calculator consider early CD withdrawal penalties or Treasury price moves?

No. It assumes you hold both investments to maturity and earn the stated yield. Early CD withdrawals can incur penalties, and Treasuries bought or sold on the secondary market can generate capital gains or losses that change your real-world return.

finance calculator

Treasury vs CD After-Tax Yield Calculator

Compare after-tax yields of Treasuries (state tax-free) vs taxable CDs using your federal and state tax rates.

Results

Treasury after-tax yield: 3.42%
CD after-tax yield: 3.61%
Higher after-tax yield: cd

Overview

This Treasury vs CD after-tax yield calculator helps you compare the return you actually keep in a taxable account. Treasuries are generally exempt from state income tax, while CD interest is usually taxed at both the federal and state level—so a lower-yield Treasury can sometimes beat a higher-yield CD once you adjust for your personal tax rates.

How to use this calculator

Identify a Treasury you’re considering (for example, a 6-month T-bill or 2-year note) and note its yield or APY from your broker or TreasuryDirect.
Find a CD with a similar term (for example, a 6-month or 2-year CD) and note its yield or APY.
Enter the Treasury yield and CD yield into the calculator.
Enter your marginal federal tax rate and your marginal state tax rate. If your state does not tax interest, enter 0 for the state rate.
Review the Treasury after-tax yield and CD after-tax yield, along with the label showing which one is higher after tax.
Adjust yields or tax rates to explore how changes in the rate environment or moving between states might change which option is preferable.

Inputs explained

Treasury yield (%): The annual yield or APY on the Treasury you plan to buy. Use a yield that matches the CD’s term (for example, both 1-year) for a fair comparison.
CD yield (%): The annual percentage yield on a bank or brokered CD with a similar maturity. Make sure the CD term closely matches the Treasury’s maturity so you are comparing like with like.
Federal tax rate (%): Your marginal federal income tax rate on ordinary income. Treasury and CD interest is typically taxed at this rate in taxable accounts.
State tax rate (%): Your marginal state income tax rate. Treasuries are generally exempt from state income tax, while CD interest is usually taxable at this rate.

Outputs explained

Treasury after-tax yield: The Treasury’s yield after applying federal income tax but with no state tax. This reflects the effective annual return you keep from Treasuries in a taxable account at your federal rate.
CD after-tax yield: The CD’s yield after applying both federal and state income taxes using a combined-rate formula. This is the effective annual return you keep from CDs in a taxable account.
Higher after-tax yield: A label indicating whether Treasuries, CDs, or neither (Equal) have the higher after-tax yield given your inputs.

How it works

You enter the quoted Treasury yield and a comparable CD yield as annual percentages (for example, 4.5 and 5.0). Both should reflect similar maturities so the comparison is apples-to-apples.

You also enter your marginal federal and state income tax rates on ordinary income. These are the rates that apply to the last dollars of interest you earn.

For Treasuries, the calculator assumes interest is taxable at the federal level but exempt from state and local income tax in most cases. Treasury after-tax yield is computed as: Treasury yield × (1 − federal tax rate).

For CDs, interest is typically taxed at both federal and state levels. To avoid double-counting, the calculator applies a combined rate formula: CD after-tax yield = CD yield × (1 − federal − state + federal × state), which correctly models the interaction between separate tax systems.

Once the after-tax yields are calculated for both instruments, the tool compares them and outputs which option has the higher after-tax yield given your inputs (Treasury, CD, or Equal).

The comparison focuses on yield, not price changes or early withdrawal penalties, and assumes you hold each investment long enough to realize the quoted annual return.

Formula

Let T = Treasury yield (decimal), C = CD yield (decimal), F = federal tax rate (decimal), and S = state tax rate (decimal).\n\nTreasury after-tax yield = T × (1 − F)  // state tax-exempt\nCD after-tax yield = C × (1 − F − S + F × S)  // combined federal + state\nHigher option = Treasury if Treasury after-tax > CD after-tax; CD if CD after-tax > Treasury after-tax; Equal otherwise

When to use it

Choosing between Treasury bills or notes and bank CDs for short- to intermediate-term savings held in a taxable brokerage account.
Evaluating a promotional CD rate at your bank against current Treasury yields to see which leaves more yield after your state taxes.
Understanding how moving to a higher- or lower-tax state changes the relative attractiveness of Treasuries versus CDs without changing nominal yields.
Helping explain to clients or family why a lower nominal Treasury yield can still be competitive with or superior to a higher CD yield after accounting for state tax.
Comparing brokered CDs and Treasuries available in a brokerage platform when building a laddered cash or fixed income strategy in taxable accounts.

Tips & cautions

Match terms as closely as possible: compare a 1-year Treasury with a 1-year CD, not a 3-month instrument with a 5-year CD.
In high state-tax brackets, Treasuries can close the gap or even win after tax against CDs with slightly higher nominal yields because their interest is state tax-free.
Inside tax-advantaged accounts (IRAs, 401(k)s, HSAs), pretax comparisons are more appropriate, because federal and state taxes don’t apply annually—look at gross yields instead.
Remember that CDs often carry early-withdrawal penalties if you need funds before maturity, while Treasuries can be sold in the secondary market at a gain or loss. This calculator focuses on yield, not liquidity or penalty risk.
Use your marginal tax rates as a guide, but if your income fluctuates, consider testing several federal/state rate combinations to see when Treasuries start to beat CDs or vice versa.
This tool assumes straightforward marginal tax treatment of interest and does not simulate full tax returns, AMT exposure, phase-outs, or local (city/county) income taxes.
It does not incorporate early withdrawal penalties for CDs, potential call features, or price volatility for Treasuries sold before maturity.
The comparison ignores reinvestment risk, inflation, and differences in credit risk between U.S. Treasuries and bank CDs (including FDIC/NCUA insurance limits).
Tax rules and rates can change; the calculator reflects only the static rates you enter and should not be relied on for long-term tax planning.
The formula treats all interest as ordinary income and does not account for special state rules or exemptions beyond the standard Treasury state tax exemption.

Worked examples

Example 1: 4.5% Treasury vs 5.0% CD, 24% federal, 5% state

Treasury yield T = 4.5% (0.045), CD yield C = 5.0% (0.05), F = 24% (0.24), S = 5% (0.05).
Treasury after-tax = 0.045 × (1 − 0.24) = 0.045 × 0.76 ≈ 0.0342 (3.42%).
CD after-tax = 0.05 × (1 − 0.24 − 0.05 + 0.24 × 0.05) = 0.05 × 0.722 ≈ 0.0361 (3.61%).
In this scenario, the CD still offers a slightly higher after-tax yield than the Treasury.

Example 2: 5.0% Treasury vs 5.1% CD, 32% federal, 0% state (no state income tax)

T = 5.0% (0.05), C = 5.1% (0.051), F = 32% (0.32), S = 0.
Treasury after-tax = 0.05 × (1 − 0.32) = 0.05 × 0.68 = 0.034 (3.40%).
CD after-tax = 0.051 × (1 − 0.32 − 0 + 0.32 × 0) = 0.051 × 0.68 ≈ 0.03468 (3.47%).
With no state income tax, the higher-yielding CD still wins after tax, but the gap is small.

Example 3: High-tax state—4.7% Treasury vs 5.1% CD, 24% federal, 10% state

T = 4.7% (0.047), C = 5.1% (0.051), F = 24% (0.24), S = 10% (0.10).
Treasury after-tax = 0.047 × (1 − 0.24) = 0.047 × 0.76 ≈ 0.0357 (3.57%).
CD after-tax = 0.051 × (1 − 0.24 − 0.10 + 0.24 × 0.10) = 0.051 × 0.684 ≈ 0.0349 (3.49%).
Here the Treasury actually delivers the higher after-tax yield even though its headline rate is lower than the CD’s.

Deep dive

Use this Treasury vs CD after-tax yield calculator to see which investment leaves you with a higher effective return in a taxable account. Enter Treasury and CD yields along with your federal and state tax rates to compare after-tax yields and identify the better choice.

The tool is especially helpful for investors in high-tax states who are weighing the state tax exemption on Treasuries against higher headline CD rates, as well as for anyone evaluating brokered CDs versus Treasuries inside a taxable brokerage account.

FAQs

Are Treasuries always better than CDs in high-tax states?: Not necessarily. While Treasuries benefit from state tax exemption, a CD with a substantially higher nominal yield can still come out ahead after tax. This calculator quantifies the trade-off for your specific yields and tax rates.
Which tax rates should I use in the calculator?: Use your marginal federal and state income tax rates on ordinary income. If you are unsure, you can approximate them from current tax tables or ask a tax professional, then run a few scenarios to see how sensitive the result is to your exact bracket.
Does this calculator handle municipal bonds or other tax-free securities?: No. Municipal bonds and other tax-exempt securities have different federal and state tax rules, including potential AMT considerations. This tool is focused specifically on Treasuries versus taxable CDs.
What if I hold Treasuries or CDs in an IRA, 401(k), or HSA?: In tax-advantaged accounts, interest is not taxed annually at your marginal rates; instead, taxation generally occurs on withdrawal (or not at all in some HSA/ROTH scenarios). In that context, you would compare gross yields and other factors like liquidity and credit risk rather than after-tax yield in the current year.
Does the calculator consider early CD withdrawal penalties or Treasury price moves?: No. It assumes you hold both investments to maturity and earn the stated yield. Early CD withdrawals can incur penalties, and Treasuries bought or sold on the secondary market can generate capital gains or losses that change your real-world return.

Related calculators

finance

Tax-Equivalent Yield Calculator

Convert a tax-free municipal bond yield into a taxable-equivalent yield using your federal and state tax rates.

finance

ROI Calculator

Calculate return on investment (ROI) plus annualized ROI for any holding period.

finance

CD Early Withdrawal Penalty Calculator

Estimate your net payout if you break a CD early, factoring accrued interest, the penalty, and interest you’d forfeit vs holding to maturity.

This Treasury vs CD after-tax yield calculator provides simplified estimates based on user-entered yields and tax rates. It does not model full tax returns, local taxes, AMT, penalties, price changes, or individual suitability. Always verify assumptions with your brokerage statements and consult a qualified financial or tax professional before making investment decisions.