Municipal Bonds
Interest on most municipal bonds is free of federal income tax and the 3.8% net investment income tax. Whether that helps depends on your bracket. At the top rate, a 3.5% municipal yield is worth about the same as a 5.9% taxable yield. In a lower bracket, a taxable bond often pays more.
Reviewed by Ebot Mbi, CPA, EA · Last reviewed October 9, 2026
Who it fits
- High earners in the 32%, 35% or 37% brackets, especially those also paying the 3.8% NIIT.
- Investors holding bonds in a taxable account.
- Retirees who want steady tax-free income, after checking the Social Security interaction.
- Texas residents, who can buy any state's bonds without a state tax trade-off.
Who it's not for
- Bonds held in IRAs or 401(k)s. The tax exemption is wasted there.
- Investors in the 22% bracket or below, where taxable bonds usually pay more after tax.
- Anyone who needs to sell before maturity in a rising-rate market.
How it works
State and local governments issue bonds whose interest is generally excluded from federal gross income. Because of that, municipal yields are lower than taxable yields.
Compare them with tax-equivalent yield: municipal yield divided by (1 minus your marginal rate). At 40.8% (37% plus 3.8%), a 3.5% municipal yield equals 3.5% / 0.592 = 5.91% taxable. At 24%, the same bond equals 3.5% / 0.76 = 4.61%.
If the taxable alternative pays more than the tax-equivalent yield, buy the taxable bond. If less, the municipal bond wins.
Some municipal interest is not fully exempt. Interest on certain private activity bonds is a preference item for the alternative minimum tax. Market discount on bonds bought below face value can be taxable as ordinary income when you sell or the bond matures.
For retirees, tax-exempt interest counts in the formula that decides how much Social Security is taxed.
Illustrative example
Illustrative: a married couple at a 40.8% combined marginal rate (37% plus 3.8% NIIT) has $1,000,000 to place in bonds in a taxable account. The choice: municipal bonds at 3.5% or taxable corporate bonds at 5%.
- Municipal: $1,000,000 x 3.5% = $35,000 a year, no federal tax.
- Taxable: $1,000,000 x 5% = $50,000 a year.
- Tax on taxable interest: $50,000 x 40.8% = $20,400.
- After-tax taxable income: $50,000 - $20,400 = $29,600.
- Municipal advantage: $35,000 - $29,600 = $5,400 a year.
At this bracket the municipal bonds keep about $5,400 more cash each year; at a 24% bracket the taxable bonds would win.
The rules
| Rule | Citation |
|---|---|
| Interest on state and local bonds is excluded from gross income, with exceptions for certain private activity and arbitrage bonds. | IRC §103 |
| Tax-exempt interest is not net investment income for the 3.8% tax. | IRC §1411(c) |
| Interest on specified private activity bonds is an AMT preference item. | IRC §57(a)(5) |
| Tax-exempt interest is added in figuring how much Social Security is taxable. | IRC §86(b)(2) |
Watch-outs
- Tax-exempt interest must still be reported on your return.
- Bonds bought below face value can produce taxable market discount.
- Interest paid to buy or carry tax-exempt bonds is not deductible.
- Credit and interest-rate risk are real. Tax-free income does not mean risk-free.
What we do
We compute your actual marginal rate, including NIIT and Social Security effects, and give your advisor the tax-equivalent yield to compare against. We review your 1099-INT and 1099-OID reporting and check for AMT exposure.
Questions
Are municipal bond funds also tax-free?
Dividends from a municipal fund that come from tax-exempt interest are generally tax-free. Capital gain distributions from the fund are taxable.
Does Texas tax municipal bond interest?
Texas has no personal income tax, so residents get no extra benefit from buying in-state bonds and no penalty for out-of-state bonds.
What bracket makes munis worth it?
There is no fixed line. Compare tax-equivalent yield to what taxable bonds of similar quality and maturity pay at the time. It usually favors munis at 32% and above.