A Form 1099-INT reports interest a bank, brokerage, or other payer paid you during the year, and each numbered box on it carries a specific kind of interest or withholding that lands in a specific place on your return. Below is what each of the boxes on the 1099-INT means, which ones matter most, and how the numbers move onto your Form 1040.
The Boxes Most People Will See
Five boxes carry the numbers that show up on the majority of 1099-INTs. If your form only has entries in these, your reporting is straightforward.
Box 1 — Interest Income
This is the total taxable interest the payer paid you during the year, except for interest on U.S. government obligations, which sits in Box 3. The Box 1 figure flows to Line 2b of your Form 1040.1Internal Revenue Service. Publication 550 (2025), Investment Income and Expenses
Box 2 — Early Withdrawal Penalty
If you cashed out a CD or another time deposit before it matured, the penalty the bank charged shows up here. You can deduct it as an adjustment to income on Schedule 1, which lowers your adjusted gross income whether or not you itemize.2Internal Revenue Service. IRS Courseware – Case Study 2: Penalty on Early Withdrawal of Savings
Box 3 — Interest on U.S. Savings Bonds and Treasury Obligations
Interest from Treasury bills, notes, bonds, and U.S. savings bonds is reported here rather than in Box 1. It’s taxable on your federal return, but most states exempt it from state and local income tax.3Internal Revenue Service. Instructions for Forms 1099-INT and 1099-OID
Box 4 — Federal Income Tax Withheld
When backup withholding applies, the payer takes a flat 24% out of your interest and sends it to the IRS on your behalf.4Internal Revenue Service. Topic No. 307, Backup Withholding The withheld amount lands in Box 4 and gets claimed on your return as tax already paid. Backup withholding usually starts because you gave the payer a wrong or missing Taxpayer Identification Number, or because the IRS told the payer to withhold after prior underreporting. If Box 4 has a number in it, find out which situation you’re in, because the withholding continues on future payments until the underlying issue is resolved.
Box 8 — Tax-Exempt Interest
Interest from municipal bonds issued by state and local governments goes here. It isn’t subject to federal income tax, but the IRS still requires you to report it on Line 2a of Form 1040.5Internal Revenue Service. 1040 (2025) Instructions Reporting isn’t the same as owing. The IRS uses this figure in other calculations, including whether part of your Social Security becomes taxable.
The Boxes That Trip People Up
A handful of less common boxes interact with other parts of the tax code in ways that aren’t obvious from the form itself. If any of these have numbers, slow down before filing.
Box 6 — Foreign Tax Paid (and Box 7 — Foreign Country)
If a foreign government withheld tax on your interest, that amount appears in Box 6, and the country it went to is named in Box 7. You can either deduct the foreign tax or take it as a dollar-for-dollar credit against your U.S. tax. The credit is almost always the better move. If your total foreign taxes across all your accounts are $300 or less ($600 for married filing jointly), you can claim the credit directly on Form 1040 without filing Form 1116.6Internal Revenue Service. Instructions for Form 1116 (2025) Above those thresholds you’ll need Form 1116 to work out the credit.1Internal Revenue Service. Publication 550 (2025), Investment Income and Expenses
Box 9 — Specified Private Activity Bond Interest
Interest from certain private activity bonds is exempt from regular federal income tax, and the amount is already inside the Box 8 total. Box 9 flags the slice of that interest which can trigger the Alternative Minimum Tax. If you have meaningful income from these bonds, run Form 6251 before assuming the interest is fully tax-free.7Internal Revenue Service. General Rules for Private Activity Bonds
Box 11 — Bond Premium
When you buy a taxable bond for more than its face value, the extra you paid is a premium. Box 11 shows the portion of that premium your broker amortized during the year. How you handle it depends on how the payer reported it. Sometimes the amortization is already netted against the interest in Box 1. Other times Box 1 is gross and Box 11 is listed separately, in which case you reduce the Box 1 interest by the Box 11 amount when you enter it on Schedule B.3Internal Revenue Service. Instructions for Forms 1099-INT and 1099-OID A blank Box 11 on a bond you know you bought at a premium usually means the payer already did the reduction for you.
Where Each Box Goes on Your Return
The 1099-INT does not attach to your return, but each box has a destination. Taxable interest from Box 1, along with Treasury interest from Box 3, goes on Line 2b of Form 1040. Tax-exempt interest from Box 8 goes on Line 2a.5Internal Revenue Service. 1040 (2025) Instructions
If your total taxable interest from all sources tops $1,500, you also fill out Schedule B, which lists each payer separately.8Internal Revenue Service. About Schedule B (Form 1040), Interest and Ordinary Dividends A few situations trigger Schedule B even under $1,500: bonds bought between interest payment dates, a reduction for bond premium amortization, or interest from a seller-financed mortgage.1Internal Revenue Service. Publication 550 (2025), Investment Income and Expenses
Federal tax withheld in Box 4 is claimed as a credit on the payments section of your return, reducing what you owe or increasing your refund. The early withdrawal penalty in Box 2 is an above-the-line deduction on Schedule 1, so it helps even if you take the standard deduction. Foreign tax in Box 6 becomes either a credit (usually) or a deduction. And a number in Box 9 sends you to Form 6251 to test for AMT.
Your payer must get the 1099-INT to you by January 31 following the tax year.9Internal Revenue Service. General Instructions for Certain Information Returns (2025)
How the Numbers Ripple Through the Rest of Your Return
Interest income doesn’t only fill Line 2b. It feeds other calculations.
If you collect Social Security, the IRS uses a formula to decide how much of your benefit is taxable. Half your annual Social Security is added to your other income, including taxable interest from Box 1, Treasury interest from Box 3, and tax-exempt interest from Box 8. If the total is over $25,000 (single) or $32,000 (married filing jointly), part of your Social Security becomes taxable.10Internal Revenue Service. IRS Reminds Taxpayers Their Social Security Benefits May Be Taxable This is why Box 8 still has to be reported: it counts toward this threshold even though it isn’t taxed on its own.
Private activity bond interest from Box 9 can raise your AMT liability. And because interest raises your adjusted gross income, it can shrink credits and deductions that phase out at higher income levels.
If the Form Is Missing, Late, or Wrong
If your 1099-INT hasn’t shown up by mid-February, call the payer. If you still can’t get it, use your bank or brokerage statements to work out the interest earned and report it on your return by the filing deadline. The income has to appear whether or not you’re holding the paper form.1Internal Revenue Service. Publication 550 (2025), Investment Income and Expenses
You can also pull a Wage and Income Transcript from the IRS, which compiles the 1099 data payers have filed. The transcript reflects the prior year’s filings, so current-year data isn’t there until the following year.
If the form shows a wrong amount, ask the payer to issue a corrected 1099-INT. The corrected version replaces the original. If you already filed using the wrong figure, amend with Form 1040-X within three years of your original filing date or two years from when you paid the tax, whichever is later.11Internal Revenue Service. Topic No. 308, Amended Returns