Non-taxable interest is interest income that federal law excludes from your gross income, so you owe no federal income tax on it. Most of it comes from municipal bonds issued by state and local governments, with a few narrower sources like qualifying U.S. savings bonds used for college and interest on VA insurance dividends. The catch worth knowing up front: you still have to report non-taxable interest on your return, and it can raise your Medicare premiums and push more of your Social Security benefits into taxable territory.
Where Non-Taxable Interest Comes From
The largest source by far is municipal bonds. When a state, city, county, or special district borrows money through a bond issue, the interest paid to bondholders is generally excluded from federal gross income.1Office of the Law Revision Counsel. 26 U.S.C. 103 – Interest on State and Local Bonds Bonds issued by agencies acting on behalf of a government qualify as well. The exemption typically covers borrowing for schools, highways, water systems, hospitals, and similar public infrastructure.
Two categories lose the exemption outright: private activity bonds that fail to meet federal qualification standards, and arbitrage bonds where the issuer reinvests the proceeds in higher-yielding securities.1Office of the Law Revision Counsel. 26 U.S.C. 103 – Interest on State and Local Bonds
A second source is interest on Series EE and Series I U.S. savings bonds used for qualified higher education expenses. The interest can be fully excluded, but the rules are strict.2Office of the Law Revision Counsel. 26 U.S.C. 135 – Income From United States Savings Bonds Used to Pay Higher Education Tuition and Fees The bond must have been issued after 1989 to a purchaser at least 24 years old at the time. The purchaser has to redeem the bond and use the proceeds for tuition and fees at an eligible institution in the same tax year. Room and board don’t count, and sports or hobby courses only count if they’re required for a degree. If redemption proceeds exceed qualifying expenses, the exclusion shrinks proportionally.
Income limits also apply. For 2025, the exclusion begins to phase out at modified adjusted gross income of $99,500 for single filers ($149,250 joint) and disappears at $114,500 ($179,250 joint).3Internal Revenue Service. Publication 970, Tax Benefits for Education Married taxpayers filing separately can’t claim it at all. To claim the exclusion you have to file Form 8815 with your return; skip it and you lose the benefit even if you qualify.4Internal Revenue Service. About Form 8815, Exclusion of Interest From Series EE and I U.S. Savings Bonds Issued After 1989
A narrower category: interest on insurance dividends left on deposit with the U.S. Department of Veterans Affairs is fully non-taxable, and you don’t need to report it on your return.5Internal Revenue Service. Topic No. 403, Interest Received This applies to VA life insurance policies only.
One place the exclusion does not apply, despite common belief: interest on dividends left on deposit with a private life insurance company. The dividends themselves are generally treated as a partial return of premiums and are non-taxable up to your cost basis, but any interest that accumulates on those dividends is fully taxable and must be reported.6Internal Revenue Service. Publication 525, Taxable and Nontaxable Income Once total dividends received exceed the premiums you’ve paid, the dividends themselves become taxable too.
Private Activity Bonds and the AMT
Some municipal bonds finance projects with substantial private-sector involvement, such as toll roads built through public-private partnerships or privately operated airport terminals. When these private activity bonds meet federal qualification standards, their interest stays exempt from regular income tax. But interest on most specified private activity bonds issued after August 7, 1986, is a tax preference item for the Alternative Minimum Tax.7Office of the Law Revision Counsel. 26 U.S.C. 57 – Items of Tax Preference Qualified residential rental project bonds, qualified mortgage bonds, and qualified veterans’ mortgage bonds are exceptions.
This matters more starting in 2026. The higher AMT exemption amounts under the Tax Cuts and Jobs Act sunset after 2025, so the AMT will reach more filers. Your 1099-INT reports private activity bond interest separately in Box 9, so you can see exactly how much you hold.8Internal Revenue Service. Instructions for Forms 1099-INT and 1099-OID
Federal Exemption Isn’t Always a State Exemption
Federal tax-exempt status doesn’t automatically carry over to your state return. Most states exempt interest on bonds issued within their own borders but tax interest on bonds issued elsewhere. If you live in a state with income tax and hold out-of-state municipal bonds, expect to owe state tax on that interest. The after-tax value of a “tax-free” bond depends heavily on where you live and where the bond was issued.
Why You Still Have To Report It
Non-taxable interest doesn’t add to the tax you owe on the interest itself, but it feeds into two other calculations that do cost real money.
Social Security Benefit Taxation
The IRS uses “provisional income” to decide how much of your Social Security is taxed. Provisional income equals your adjusted gross income, plus half your Social Security benefits, plus all of your tax-exempt interest.9Office of the Law Revision Counsel. 26 U.S.C. 86 – Social Security and Tier 1 Railroad Retirement Benefits The thresholds have never been indexed for inflation:
- Single filers: provisional income between $25,000 and $34,000 makes up to 50% of benefits taxable; above $34,000, up to 85% is taxable.
- Joint filers: the 50% band runs from $32,000 to $44,000; above $44,000, up to 85% is taxable.
A retiree with $20,000 in Social Security and $15,000 in municipal bond interest might assume they owe nothing in federal tax. The bond interest, though, pushes provisional income past the point where half the Social Security becomes taxable. This is the main reason the IRS wants tax-exempt interest on your return in the first place.
Medicare IRMAA
Medicare Part B and Part D premiums rise for higher-income beneficiaries through the Income-Related Monthly Adjustment Amount. IRMAA uses modified adjusted gross income, and MAGI explicitly includes tax-exempt interest from Line 2a of Form 1040.10Social Security Administration. Modified Adjusted Gross Income (MAGI) For 2026 premiums (based on your 2024 return), surcharges begin at $109,000 for single filers and $218,000 for joint filers. Because IRMAA looks back two years, a large bond redemption or a one-time spike in tax-exempt interest can raise your Medicare premiums two years later.11Social Security Administration. Medicare Income-Related Monthly Adjustment Amount – Life-Changing Event
How To Report Non-Taxable Interest
Financial institutions send Form 1099-INT with tax-exempt interest in Box 8 and any private activity bond interest in Box 9.8Internal Revenue Service. Instructions for Forms 1099-INT and 1099-OID If you hold tax-exempt bond mutual funds, exempt-interest dividends show up in Box 12 of Form 1099-DIV instead. Transfer the total to Line 2a of Form 1040.12Internal Revenue Service. Instructions for Schedule B (Form 1040) The amount doesn’t flow into your adjusted gross income, but it’s the number the Social Security and IRMAA calculations reach for.
Leaving Line 2a blank isn’t harmless. The IRS matches your return against the 1099-INT data it receives, and a mismatch can trigger a notice. Failing to include 1099 information can be treated as negligence and carries an accuracy-related penalty of 20% of any resulting underpayment.13Internal Revenue Service. Accuracy-Related Penalty Even though the interest itself isn’t taxed, an omission can cause the IRS to recalculate how much of your Social Security should have been taxed, producing an underpayment you didn’t expect.