Tax-Equivalent Yield Calculator
Created by: James Porter
Last updated:
Compare a municipal bond’s tax-free yield with the after-tax yield of a taxable bond using your federal, state, and local tax assumptions.
Tax-Equivalent Yield Calculator
FinanceCompare tax-free municipal yield with taxable bond yield after federal, state, and local tax drag.
What is a Tax-Equivalent Yield Calculator?
A tax-equivalent yield calculator converts a tax-free municipal bond yield into the taxable yield an investor would need to earn to match that after-tax result.
It is one of the clearest ways to compare municipal bonds with taxable fixed-income alternatives.
This matters because headline yields can be misleading when tax treatment differs.
A taxable bond may show a higher stated yield, yet still leave the investor with less net income after federal, state, and local taxes are considered.
A useful tax-equivalent yield tool should show the combined effective tax rate, the tax-equivalent yield of the municipal bond, and the after-tax yield of the taxable bond so the comparison is explicit.
How the Tax-Equivalent Yield Calculation Works
The calculator combines the entered tax rates into a single effective tax drag, then divides the municipal yield by one minus that combined rate.
The result is the taxable yield required to match the municipal bond's tax-free income on an apples-to-apples basis.
It also applies the same combined tax rate to the taxable bond yield so you can see what the taxable alternative is worth after taxes.
That side-by-side comparison is often more useful than looking at either yield in isolation.
Core tax-equivalent yield relationships
Combined tax rate = 1 - (1 - federal rate) x (1 - state rate) x (1 - local rate)
Tax-equivalent yield = municipal yield / (1 - combined tax rate)
Taxable after-tax yield = taxable yield x (1 - combined tax rate)
Example Scenarios
Example 1: High-bracket investor
Higher marginal tax rates usually make municipal income more competitive because the taxable alternative loses more yield to taxes.
Example 2: State-tax impact
A modest state tax can be enough to move the break-even point between a muni bond and a taxable corporate bond.
Example 3: Portfolio income choice
Advisors can use tax-equivalent yield to explain why a lower stated municipal yield may still be the stronger net-income option.
How People Use This Calculator
- Compare municipal bonds with taxable bonds on a consistent after-tax basis.
- Evaluate whether a high tax bracket changes the better income choice.
- Support account-location decisions between taxable and tax-advantaged portfolios.
- Explain muni-versus-taxable tradeoffs in client or internal portfolio discussions.
Tips for Better Tax-Equivalent Yield Analysis
Use tax rates that actually reflect the investor's marginal situation.
Tax-equivalent yield is only as good as the bracket assumptions behind it.
Do not stop at the tax result alone.
Municipal and taxable bonds can still differ in credit risk, duration, liquidity, and call provisions, so the higher after-tax yield is not automatically the better investment.
Frequently Asked Questions
What is tax-equivalent yield?
Tax-equivalent yield is the taxable yield needed to match a tax-free municipal bond yield after taxes.
Why does it matter?
It allows investors to compare municipal bonds and taxable bonds on a more comparable after-tax basis.
How are taxes handled?
This calculator uses the federal, state, and local rates you enter to estimate a combined effective tax drag.
Is the higher tax-equivalent yield always the better choice?
No. Credit quality, duration, liquidity, and call features still matter when comparing bonds.
Sources and References
- Investor education covering municipal bond taxation and tax-equivalent yield.
- General personal-finance references on comparing taxable and tax-free income streams.
Planning Note
Tax-Equivalent Yield Calculator is a planning estimate. Live bond prices can differ because of settlement timing, call provisions, credit spreads, taxes, and market liquidity.