Tax-Equivalent Yield Calculator 2026: Municipal Bond & Fixed Income Workbench

Tax-equivalent yield (TEY) is the pre-tax yield a taxable bond would need to pay in order to give you the same after-tax return as a tax-exempt municipal bond. It matters because raw yield numbers are misleading across bond types — a 3.85% muni and a 5.80% corporate are not directly comparable until you strip out the taxes each one triggers. The formula is simple: TEY = Muni Yield ÷ (1 − Your Marginal Tax Rate). Once you calculate TEY, you can compare apples to apples.

Always use your marginal tax rate — the rate that applies to the next dollar of income you earn. Because bond interest is ordinary income that sits on top of all your other income, every dollar of new interest is taxed at your highest bracket. Using your effective (average) rate would significantly understate the actual tax cost and make taxable bonds look more competitive than they truly are for your situation.

The Net Investment Income Tax (NIIT) is a 3.8% federal surtax on investment income — including interest from taxable bonds — for taxpayers whose modified adjusted gross income (MAGI) exceeds $200,000 (single) or $250,000 (married filing jointly). It does not apply to municipal bond interest. This means high earners need to add 3.8% to their effective federal drag on any taxable bond, making the TEY advantage of munis meaningfully larger than the headline federal bracket alone would suggest.

Certain private activity bonds (PABs) — munis issued to fund privately-used projects like airports, sports stadiums, or certain hospital expansions — generate interest that is subject to the Alternative Minimum Tax (AMT). If you hold these bonds and are subject to the AMT, part of your muni interest becomes taxable, reducing the expected tax advantage. General obligation (GO) bonds issued directly by states or municipalities for public purposes carry no AMT risk and are fully tax-exempt for most investors.

The general rule of thumb is that munis become competitive at the 24% federal bracket and above, and become significantly advantageous at 32% and higher. Below 24%, taxable bonds typically win on an after-tax basis because the muni yield discount isn’t worth the trade-off. However, the state income tax layer changes this calculation considerably — an investor in a 9–13% state tax bracket may find munis competitive even at the 22% federal bracket once combined tax drag is fully stacked.

Treasury interest is exempt from all state and local income taxes by federal law, but is still subject to federal income tax. In states with high income tax rates — California (up to 13.3%), New York (up to 10.9%), New Jersey (up to 10.75%) — the state-tax exemption on Treasuries is extremely valuable. When Treasury yields are elevated relative to muni yields, an investor in a high-tax state might find that the Treasury’s state exemption more than compensates for its lack of federal exemption. This calculator captures that comparison precisely.

Generally no — this is one of the most common bond investing mistakes. Tax-deferred accounts like IRAs and 401(k)s already shelter all income from taxes until withdrawal. Placing tax-exempt munis inside these accounts wastes their tax advantage entirely, because you already aren’t paying annual taxes on the income. The smart structure is: hold munis in taxable brokerage accounts where their tax exemption provides real after-tax value, and reserve your tax-deferred space for higher-yielding taxable bonds like corporates and Treasuries.

The calculator multiplies your investment amount by the after-tax yield for each bond type. For example, if your in-state muni after-tax yield is 3.61% and you invest $250,000, the estimated annual after-tax income is $9,025. This number lets you compare actual dollars across bond types rather than abstract percentages — which is how most investors actually make portfolio decisions. Note that this is an estimate based on current yields, not a guarantee of future income.

The muni-to-Treasury ratio compares the yield of a municipal bond to the yield of a Treasury of the same maturity, expressed as a percentage. A ratio of 80% means the muni yields 80 cents for every dollar the Treasury yields. Historically, ratios below 80% suggest munis are expensive relative to Treasuries, while ratios above 90–100% indicate munis are cheap and offer strong after-tax value even for moderate-bracket investors. Watching this ratio helps you time muni purchases and recognize when the tax advantage is especially pronounced.

Yes — dramatically. Consider two investors both in the 35% federal bracket. One lives in Texas (0% state income tax) and the other in California (13.3% top rate). The Texan’s combined tax drag on a corporate bond is roughly 38.8% (35% + 3.8% NIIT). The Californian’s drag is 52.1% (35% + 13.3% + 3.8%). That difference makes a 4% in-state California muni worth a taxable-equivalent of roughly 8.35% for the California investor — while the same bond is worth only 6.54% to the Texan. State tax is the single biggest variable most online TEY calculators ignore.

The de minimis rule is a rarely discussed trap for muni bond buyers on the secondary market. If you buy a muni bond at a discount that is more than 0.25% per year remaining to maturity, the entire discount (the difference between your purchase price and par) is taxed as ordinary income at maturity — not as tax-free income or even a capital gain. For example, buying a 10-year muni at more than 2.5 points below par triggers ordinary income treatment. This can quietly eliminate most of the expected tax benefit if you’re purchasing discounted munis in the secondary market.

Many investors overlook local income taxes entirely, but they can be meaningful — New York City levies up to 3.876%, Philadelphia 3.75%, and Detroit 2.4%. Local taxes apply to most taxable bond income and often to out-of-state munis. In-state munis issued by your own city or county are sometimes exempt from local tax too, though this varies. Adding your local rate into this calculator can shift the after-tax yield comparison by a full percentage point in high-local-tax cities, making in-state munis even more attractive than federal-only TEY calculations show.

Yes, with one important caveat. Most national muni bond funds — like iShares MUB or Vanguard’s VWITX — hold bonds from multiple states. The fund’s 30-day SEC yield is generally federal tax-exempt, but the state-tax treatment depends on the percentage of the fund’s income derived from your home state’s bonds. If less than a threshold percentage (often 50%) comes from your state, some states won’t grant the state-tax exemption on any of the income. Check the fund’s annual tax letter for the state-by-state breakdown, or use a single-state muni fund if state-tax exemption is a priority.

Like all fixed-income securities, muni bond prices move inversely to interest rates. When rates rise, existing bond prices fall because new bonds are issued at higher yields, making older lower-coupon bonds less valuable. A bond with a 10-year duration loses roughly 10% of its market value for every 1% rise in yields. This price risk is especially relevant if you might need to sell before maturity. If you’re a buy-and-hold investor, price fluctuations don’t affect your locked-in yield — but if you need liquidity, rising rates can turn a tax-efficient income strategy into an unexpected capital loss.

This is a critical planning point that many retirees miss. Although muni bond interest is not included in your taxable income, it is included in the IRS’s “combined income” formula used to determine what percentage of your Social Security benefits get taxed. Combined income = adjusted gross income + nontaxable interest + half of Social Security benefits. Earning large amounts of muni income can push retirees over the $25,000 (single) or $32,000 (MFJ) thresholds that cause up to 85% of Social Security benefits to become taxable — creating an indirect tax cost from “tax-free” bonds.

Tax-loss harvesting means selling a bond that has declined in value to realize a capital loss, then buying a similar (but not “substantially identical”) bond to maintain your portfolio exposure. Those losses can offset capital gains or up to $3,000 of ordinary income per year, with excess losses carrying forward indefinitely. Muni bonds can be harvested just like any other bond — sell a California GO bond at a loss and immediately replace it with a different California GO bond of similar maturity to stay invested while banking the tax deduction. Just be careful to avoid the wash-sale rule, which disallows losses if you repurchase the same or substantially identical security within 30 days.

When the TEY gap vs. corporate yield is negative, it means the muni’s tax-equivalent yield is lower than the taxable corporate bond’s headline yield. In plain terms, the corporate bond still wins after taxes at your current tax rate. This typically happens when your combined tax rate is below 30%, when the corporate yield spread over munis is unusually wide, or when you’re comparing lower-quality munis to investment-grade corporates. A positive TEY gap means the muni clears the taxable benchmark — the higher the positive number, the stronger the case for holding munis in a taxable account.

Both general obligation (GO) bonds and revenue bonds are generally federal-tax-exempt, but they differ in credit backing and AMT risk. GO bonds are backed by the full taxing power of the issuing government — they’re considered safer and almost never trigger AMT. Revenue bonds are repaid solely from a specific income stream (like toll revenue, hospital fees, or utility payments). Some revenue bonds issued for private-use purposes qualify as private activity bonds, which means their interest may be an AMT preference item. Before buying any revenue bond, check the official statement to confirm whether it is AMT-exempt or AMT-subject.

Inflation erodes the purchasing power of any fixed coupon payment. A muni paying 3.85% when inflation runs at 3.5% delivers a real after-tax return of just 0.35% — nearly nothing. Unlike TIPS (Treasury Inflation-Protected Securities), standard munis offer no inflation adjustment. This is why muni bonds are generally best suited as a tax-efficient income tool for investors already in high brackets, rather than a total-return strategy. When real yields are deeply negative — meaning inflation exceeds the muni yield — even tax-free income loses ground to the cost of living over time.

A callable bond gives the issuer the right to redeem (pay off) the bond before its stated maturity date, usually after a lockout period of 5–10 years. Most muni bonds are callable. This matters for yield calculations because if rates fall, issuers will call in their high-coupon bonds and reissue at lower rates — which means you get your principal back early and must reinvest at a lower yield. Always compare yield to call (YTC) alongside yield to maturity (YTM) for callable munis. When a bond trades at a premium (above par), the yield to call is typically the more conservative and realistic figure to use.

A fund’s 30-day SEC yield is a standardized, annualized figure that reflects net investment income earned over the past 30 days — it’s the most apples-to-apples number to use for fund comparisons, and it’s the right input for this calculator. It already reflects the fund’s expense ratio drag. For individual bonds, use the yield to maturity (YTM) rather than the coupon rate, especially if the bond trades at a premium or discount to par. One additional difference: fund yields fluctuate daily as the portfolio is rebalanced, while a held-to-maturity individual bond locks in your yield at purchase.

Most individual investors should focus on investment-grade munis rated Baa/BBB or higher by Moody’s, S&P, or Fitch. Bonds rated Aaa/AAA to Aa/AA carry the lowest default risk and are appropriate for capital-preservation portfolios. Higher-yielding high-yield or “junk” munis (rated Ba/BB and below) offer larger spreads but carry meaningful default risk — the higher TEY you calculate may never materialize if the issuer defaults. Historically, muni default rates are far lower than corporate bonds at the same rating, but they do occur, particularly in revenue bonds tied to struggling projects or fiscally stressed municipalities.

When an investor dies holding bonds, their heirs typically receive a step-up in cost basis to the fair market value at the date of death. For taxable bonds like Treasuries or corporates, this eliminates embedded capital gains entirely — so any price appreciation above the original purchase price escapes capital gains tax. For muni bonds, the step-up also applies to any market price appreciation, though the interest income itself was already tax-free. This makes munis held in taxable estates somewhat less advantaged by the step-up than highly appreciated corporate bonds, since much of the muni’s return was already tax-free income rather than unrealized gain.

Yes. A fast mental shortcut: divide the muni yield by (1 − your federal rate alone) to get a rough TEY, then compare to the taxable yield. If the taxable bond yields less than that TEY, the muni wins; if it yields more, run the full calculation including state, local, and NIIT because the answer may still flip. A more refined rule for 35%+ bracket investors in moderate-tax states: any muni trading within 75–80% of a comparable Treasury yield is likely competitive after state taxes. Below 70%, the muni is probably priced rich and you’d be better served by a Treasury or high-grade corporate in a tax-sheltered account.

Municipal bond interest is reported to you on Form 1099-INT, Box 8 (tax-exempt interest) and Box 13 (if any portion is AMT-related private activity bond interest). You report the total tax-exempt amount on Form 1040, Line 2a — it shows up on your return but is not added to taxable income. However, as noted earlier, it is used in the Social Security combined income formula. If you have PAB interest in Box 13, you must also enter that amount on Form 6251 (AMT) as a preference item. Keep all 1099s from brokerage accounts and fund companies to ensure nothing is missed at filing time.

Original issue discount (OID) occurs when a bond is issued below its face value — for example, a zero-coupon muni issued at $600 that matures at $1,000. The $400 discount is the OID. For tax-exempt muni bonds, OID that accretes (builds up) over the life of the bond is generally also federal tax-exempt, treated the same as regular muni interest. This is one reason zero-coupon munis are popular in tax-deferred estate strategies — no cash interest is distributed, the full discount accretes tax-free, and the investor receives par at maturity. State tax treatment of muni OID varies, so confirm your state’s rules for out-of-state zero-coupon munis.

Bond yields shift daily, and the relative attractiveness of munis vs. Treasuries vs. corporates can change significantly over a single quarter. A good practice is to re-run your TEY comparison at least quarterly, or any time one of the following occurs: the Federal Reserve changes the federal funds rate, your marginal tax bracket changes (job change, business income swing, Roth conversion), you move to a different state, or the muni-to-Treasury ratio crosses a major threshold (like 90% or above). Downloading a PDF from this calculator and saving it with a date stamp makes it easy to compare your current scenario against prior calculations.

Not all municipal bonds are tax-exempt. Taxable municipal bonds are issued by state and local governments but do not qualify for federal tax exemption — typically because they fund projects that don’t meet IRS criteria for tax-exempt status, such as pension obligation bonds, economic development bonds, or refunding bonds issued after certain IRS deadlines. Taxable munis generally offer higher yields than tax-exempt munis to compensate investors for the tax liability, and they’re often held in tax-deferred accounts. This calculator focuses on traditional tax-exempt munis — if you’re evaluating taxable munis, treat them the same as corporate bonds in the taxable yield input field.