Municipal Bonds Tax-Free Income 2026: SALT Cap Math

Municipal bonds pay you interest the IRS doesn’t tax — and in November 2026, two things changed the math at once. The SALT deduction cap jumped to $40,400 under the One Big Beautiful Bill Act, and muni yields fell sharply after the strongest October for the market in decades. A 10-year AAA municipal bond yielded 3.24% on November 6, 2026, down from 4.23% on September 29. That sounds low next to a 10-year Treasury at 5.15% — until you run the tax-equivalent math. At the top 37% federal bracket, a 4% tax-free yield behaves like a 6.35% taxable yield. This article works out exactly when that trade wins, when it loses, and how to buy munis without the usual traps.

The SALT cap changed in 2026 — and it changes the muni question

For eight years, the SALT deduction was capped at $10,000. The One Big Beautiful Bill Act (OBBBA, P.L. 119-21, signed July 4, 2025) rewrote that number: the cap rose to $40,000 for 2025 and $40,400 for 2026, then rises 1% a year through 2029 ($40,804 in 2027, $41,212 in 2028, $41,624 in 2029) before reverting to $10,000 in 2030 unless Congress acts.

That matters for muni buyers because the SALT cap and the muni exemption are two sides of the same coin. Both are about how much of your state and local tax burden the federal government lets you escape. When the cap was $10,000, a high earner in California or New York lost most of their state-tax deduction, which made the muni exemption — interest that never shows up on your federal return at all — unusually valuable. Now that the cap is $40,400, more of your state taxes are deductible, which slightly reduces the relative edge of munis. Slightly. It doesn’t erase it, because the exemption and the deduction work differently: the deduction only helps if you itemize, and it only offsets tax on income you already earned. The muni exemption removes the income itself.

Three details of the new cap deserve attention before you do any muni math:

The phase-out. If your modified adjusted gross income (MAGI) tops $505,000 in 2026, the cap shrinks by 30 cents for every dollar above that line, and it can’t fall below $10,000. The phase-out finishes at roughly $606,333 of MAGI — above that, you’re back to the old $10,000 cap and the muni exemption is worth every bit as much as it was before. Married filing separately, the numbers halve: a $20,200 cap, a $252,500 threshold, and a $5,000 floor.

The itemizing hurdle. The cap only helps if your itemized deductions beat the standard deduction — $16,100 for single filers and $32,200 for married couples filing jointly in 2026. Plenty of people with $40,400 of state taxes still take the standard deduction, because their other itemized deductions are thin. If you take the standard deduction, the SALT cap change does nothing for you — but the muni exemption still works, because it never depended on itemizing in the first place.

The sunset. The elevated cap is temporary. After 2029 it reverts to $10,000. A muni bond you buy today can pay tax-free interest for 10, 20, or 30 years. The SALT cap you compare it against will change at least once during that bond’s life. That’s a reason to buy munis for the exemption itself, not for a one-year quirk in the cap.

What a municipal bond actually pays you

A municipal bond is a loan to a state, city, county, school district, or public authority. You lend the money, the issuer pays you interest — usually twice a year — and returns your principal at maturity. The part that makes munis a passive-income tool is the tax treatment: interest on most municipal bonds is exempt from federal income tax under Internal Revenue Code Section 103. The IRS explains the federal tax treatment of municipal-bond interest in Publication 550, Investment Income and Expenses. If the bond was issued by your state of residence, the interest is usually exempt from your state income tax too. In a handful of places — New York City is the famous one — a bond issued by your own city can be exempt from local tax as well, which is how the phrase “triple tax-free” gets used.

That exemption is the entire product. Munis almost always pay a lower headline yield than a comparable taxable bond, because the market prices the tax break in. The question is never “does a muni pay more than a Treasury?” — it usually doesn’t, on paper. The question is “does a muni pay more than a Treasury after I pay tax on the Treasury?” And the answer depends entirely on your bracket.

A few mechanics worth knowing before you compare anything:

• Minimums are real. Individual muni bonds typically come in $5,000 face-value increments. Funds and ETFs have no such floor, which is why most first-time muni buyers start there.
• Not every muni is fully exempt. Private-activity bonds — the ones that fund airports, stadiums, and some hospitals — can be subject to the Alternative Minimum Tax. A fund’s fact sheet will tell you how much of its income is AMT-subject; check it if you pay AMT.
• Munis are not FDIC-insured. A bond is only as good as its issuer. Defaults are rare — investment-grade muni default rates run far below corporate bonds — but they happen, and the muni market has frozen up in panics, notably in 2008 and March 2020, when sellers briefly couldn’t find buyers at any price. Don’t treat munis as a savings account.
• The exemption is worthless inside a retirement account. Interest in an IRA or 401(k) is already tax-deferred, so putting a muni there gives up yield for a tax break you can’t use — and the money comes out as ordinary income anyway. Munis belong in taxable brokerage accounts. Taxable bonds belong in the IRA. That placement rule is one of the easiest wins in all of personal finance, and it’s free.

The one calculation: tax-equivalent yield

Everything in this article comes down to one formula:

Tax-equivalent yield = muni yield ÷ (1 − your marginal tax rate)

If a muni pays 4% and your federal marginal rate is 24%, the taxable bond would need to pay 4% ÷ (1 − 0.24) = 5.26% to leave you with the same after-tax income. If it pays less than that, the muni wins. If it pays more, the taxable bond wins.

Here is that math at early-November 2026 yields, using a 4.00% muni yield — roughly where national muni funds sat (their 30-day SEC yields ranged from 3.76% to 4.11% as of November 5, 2026) — against the 10-year Treasury at 5.15% (November 13, 2026):

Two things jump out. First, the break-even sits around the 22% bracket — which matches an independent September 2026 analysis that put the break-even against the 10-year Treasury at roughly a 15% marginal rate when muni yields were higher relative to Treasuries. Second, the advantage compounds fast as your bracket rises. At the top rate plus the 3.8% net investment income tax, a 4% muni behaves like a 6.76% taxable bond — better than the 5.96% that investment-grade corporate bonds averaged on November 12, 2026.

Now add your state. If you live in California and buy a California bond, the interest escapes state tax too. A 3.60% in-state muni for a Californian in the 35% federal bracket plus 10.3% state bracket works out to roughly a 6.60% taxable-equivalent yield. For a top-bracket New Yorker, the same math pushes past 7.5%. That is why the muni conversation is really a high-tax-state conversation: the same bond is a mediocre deal in Texas or Florida (no state income tax to escape) and a genuinely good one in California, New York, or New Jersey.

A worked example, because the table above is abstract and your money isn’t. Say you put $50,000 into a national muni fund yielding 4.00% and you’re in the 32% bracket. You collect $2,000 a year, tax-free. A taxable bond fund yielding 5.15% would pay $2,575 — but after 32% federal tax you keep $1,751. The muni puts $249 more in your pocket every year. Scale that to $200,000 and it’s about $1,000 a year, every year, for as long as you hold the position. At the 24% bracket, the same comparison flips to nearly a tie — $2,000 tax-free versus $1,957 after tax — which is why the bracket check comes before everything else.

Munis vs the alternatives right now

Tax-free income has competition in November 2026, and a fair article compares munis against all of it.

Treasuries. The 10-year Treasury yielded 5.15% on November 13, 2026. Treasury interest is exempt from state tax but fully taxable federally, which is the mirror image of a muni. For a 22% bracket investor in a no-income-tax state, the Treasury wins outright. For a 32%+ investor in a high-tax state, the muni wins. The two are the cleanest head-to-head in fixed income, and the bracket table above settles it.

Treasury bills. Short-term T-bills are the cash-parking alternative, and the site’s own Treasury bills after-tax guide walks through their after-tax math in detail. Bills are better for money you need within a year. Munis are better for money you can leave alone for years, because their advantage is the exemption compounding over time, not a single rate.

I Bonds. Series I bonds issued November 1, 2026 through April 30, 2027 pay a 5.51% composite rate, including a 1.40% fixed rate — the highest fixed rate since 2006. That’s a strong headline, and the site’s I Bonds November 2026 piece covers it in full. But I Bonds cap you at $10,000 per person per year, lock your money for 12 months, and forfeit three months of interest if you cash out before five years. They’re a complement to munis, not a substitute: buy your $10,000 of I Bonds, then put the rest of your bond allocation in munis if your bracket says so.

CDs. Five-year CDs were paying roughly 4.30–4.50% in the fall of 2026, fully taxable. Against a 3.60% muni, the break-even is around the 24% federal bracket — below that, take the CD; above 32%, the muni is the obvious choice. CDs have one edge munis can’t match: FDIC insurance up to $250,000. If the guarantee matters more to you than the yield, the CD wins regardless of bracket.

Corporate bonds. Investment-grade corporates averaged 5.96% on November 12, 2026 — the highest headline yield on this list. But every dollar is taxed as ordinary income, and corporate default risk is materially higher than muni default risk. At the top bracket plus NIIT, a 4% muni’s 6.76% taxable-equivalent yield beats the corporate average outright. Below the 24% bracket, corporates usually win on yield alone.

The market just moved — October’s rally and what it means

Context matters, because muni yields in November 2026 are not where they were a month ago. October 2026 delivered the strongest monthly return for the Bloomberg Municipal Bond Index in at least 25 years — up 3.85% in a month that has averaged a small loss over the past quarter-century. The 10-year AAA muni yield fell from 4.23% on September 29 to 3.24% on November 6, and the index turned year-to-date positive (+0.43%) for the first time since August 31. Money followed: muni funds took in $286 million in the week ending November 5, favoring ETFs and investment-grade paper.

I won’t tell you to time the market, because the honest version is that nobody knows whether yields go back up. But muni income is a long game: the investors who do well buy for the exemption and hold through rate cycles, collecting tax-free coupons while yields bounce around. If the bracket math says munis win for you, the entry point matters less than the holding period.

How to buy them: funds, ETFs, or individual bonds

For most people, the practical choice is between a fund and individual bonds, and the fund wins for most first-time buyers.

Muni bond funds and ETFs are the simplest route. You get instant diversification across hundreds of issuers, professional credit research, and daily liquidity — you can sell any trading day. National funds (Vanguard Tax-Exempt Bond ETF, 0.03% expense ratio, 4.11% 30-day SEC yield as of November 5, 2026; iShares National Muni Bond ETF, 0.05%, 3.76%) work for anyone. Single-state funds exist for California, New York, New Jersey, and a few others, and they’re the way to capture the state exemption on top of the federal one — worth it if your state rate is high, pointless if your state has no income tax. Watch the expense ratio: the gap between a 0.03% fund and a 0.37% fund is real money over a decade, and it comes straight out of your yield.

Individual bonds make sense once you’re investing $50,000 or more and want control: you can build a ladder (bonds maturing in 1, 3, 5, 7, and 10 years), hold to maturity so price swings don’t matter, and pick your state’s issuers precisely. The costs are a $5,000 minimum per bond, wider bid-ask spreads for small trades, and the research burden — you’re your own credit analyst. Use the MSRB’s EMMA website (emma.msrb.org) to check a bond’s price history and official filings before you buy; it’s free, and it’s the same data the professionals use.

A simple starter setup for a 32%+ bracket investor with $25,000: put the whole amount in a low-cost national muni ETF, set dividends to reinvest, and revisit once a year. If you live in a high-tax state and your position grows past $50,000, split it — keep the national fund and add a single-state fund for the state exemption. If you ever cross $100,000, that’s when individual bonds and a ladder start to earn their complexity.

When munis are the wrong call

A good passive-income article says plainly who should skip the product, and munis have a real skip list:

• You’re in the 10% or 12% bracket. The tax break is worth almost nothing to you. Take the higher taxable yield.
• The money lives in an IRA or 401(k). The exemption is wasted there, as covered above.
• You need the money within a year. Bond prices fall when rates rise, and a fund can be down 5% in a bad quarter. Emergency funds belong in a high-yield savings account or T-bills, not munis.
• You’re chasing high-yield munis. High-yield (below-investment-grade) muni funds pay more because the issuers are riskier — distressed hospitals, speculative developments, Puerto Rico-era restructurings. The extra yield is not free. If a muni fund yields 2 points more than the investment-grade average, ask what risk you’re being paid to take.
• You’d buy private-activity bonds without checking AMT. If you pay the alternative minimum tax, the “tax-free” interest on some bonds isn’t free at all.
• You’re in a no-income-tax state and a low bracket. Both exemptions are worthless to you. A Treasury or a CD is the better buy.

A quick decision checklist

Run through this in order, and you’ll have your answer in five minutes:

1. What’s your federal marginal bracket? Below 22%, stop — munis almost certainly lose. At 24%, it’s a coin flip. At 32% and above, keep going.
2. Does your state have an income tax? If yes, and it’s 5% or more, check whether a single-state fund exists for your state — the state exemption is often worth more than the federal one.
3. Is this a taxable account? If the money is in an IRA, stop. Munis don’t belong there.
4. Can you hold for 3+ years? If not, stop. Short money belongs in T-bills or a savings account.
5. Run the formula. Take the current yield of the fund or bond you’re considering, divide by (1 − your combined marginal rate), and compare it against the best taxable yield you can actually buy today. Higher number wins.
6. Check the AMT line. If the fund holds private-activity bonds and you pay AMT, adjust the math or pick a different fund.

If you clear all six steps with munis ahead, buy them and stop second-guessing the daily yield moves. The exemption does its work quietly, year after year, and the SALT cap — whatever Congress does with it next — doesn’t change the core deal: interest the IRS never sees is the cheapest income in the tax code.

This article is general information, not professional financial or tax advice. Tax law and bond yields change frequently — the figures here are from early November 2026 sources — so confirm current rates and talk with a qualified tax professional before acting.

This article is educational, not financial or tax advice. Tax rules change, and your situation is unique — check current IRS guidance or talk to a qualified tax professional before making investment decisions.

Frequently Asked Questions

Are municipal bonds really tax-free?

The interest is exempt from federal income tax under IRC Section 103, and usually exempt from state tax if the bond was issued by your state of residence. Capital gains are different: if you sell a muni bond or fund shares for a profit, that gain is taxable. And some private-activity bonds are subject to the alternative minimum tax.

What is the SALT cap in 2026?

$40,400 for single filers, married couples filing jointly, and heads of household ($20,200 if married filing separately), under the One Big Beautiful Bill Act. It phases down once MAGI exceeds $505,000 in 2026 — falling 30 cents per dollar of excess income, with a $10,000 floor — and it reverts to $10,000 in 2030 unless Congress extends it.

How do I calculate the tax-equivalent yield?

Divide the muni yield by (1 − your marginal tax rate). A 4% muni at a 32% federal rate equals 4% ÷ 0.68 = 5.88% taxable. Add your state rate for in-state bonds — but if you itemize, use the adjusted combined rate, since state taxes are federally deductible: federal + state × (1 − federal).

Are municipal bonds safe?

Investment-grade munis have very low historical default rates, but they are not risk-free and not FDIC-insured. Their prices fall when interest rates rise, and the market can freeze in a panic, as it did in 2008 and March 2020. Diversify through a fund, stick to investment-grade issues, and don’t put money you’ll need soon into long-maturity bonds.

Should I buy individual muni bonds or a fund?

Funds and ETFs are better for most people: instant diversification, daily liquidity, and no $5,000-per-bond minimum. Individual bonds make sense above roughly $50,000–$100,000, when you want a maturity ladder and the control to hold to maturity. Check any individual bond’s price and filings on the MSRB’s free EMMA website before buying.

Do municipal bonds make sense in 2026 after the SALT cap increase?

For high earners, yes — arguably more than before in one respect: the cap’s phase-out above $505,000 of MAGI means the highest earners get almost no SALT benefit at all, so the muni exemption is their main shelter. For middle-bracket filers who can now deduct more state tax, the muni edge narrowed slightly, but the bracket table still favors munis from the 24% bracket up. The deciding factor remains your marginal rate, not the cap.