No, you do not need to attach Form 1099-INT to your federal tax return. Every bank, brokerage, or other payer that sent you one already filed a copy directly with the IRS, so your job is to report the interest accurately on Form 1040, not to forward the paperwork.1Internal Revenue Service. About Form 1099-INT, Interest Income
That’s true whether you e-file or mail a paper return. E-filing software transmits only the data you enter on Form 1040 and its schedules; there is no field for uploading the informational form itself. Paper filers don’t need to staple it on either.
The One Exception for Paper Filers
If federal income tax was withheld from your interest — shown in Box 4 of the 1099-INT as backup withholding — the IRS 1040 instructions tell you to report that withholding on Line 25b of your return.2Internal Revenue Service. 1040 (2025) Some paper filers attach the 1099-INT in that situation to document the withholding credit, but even then it isn’t strictly required. The number on Line 25b is what matters.
Backup withholding typically applies at 24% when you didn’t give the payer a valid taxpayer identification number or failed to certify that you weren’t subject to it. If Box 4 is blank or zero, this exception doesn’t touch you.
A Note on State Returns
Federal rules don’t govern what your state wants. Some states ask paper filers to include copies of 1099 forms with the state return, so check your state’s filing instructions before you throw the form away or file it. This is the one place the “don’t attach” answer flips.
Where the Interest Actually Goes on Your Return
Form 1040 has two lines for interest income: Line 2a for tax-exempt interest and Line 2b for taxable interest.3Internal Revenue Service. Form 1040, U.S. Individual Income Tax Return How you get to the numbers on those lines depends on how much interest you earned in total.
Under $1,500 in Taxable Interest
Add up the Box 1 amounts from every 1099-INT you received and enter the total directly on Line 2b. If any of your forms show tax-exempt interest in Box 8, add those together and put the total on Line 2a. No extra form required.
$1,500 or More, or Special Situations
Once your taxable interest crosses $1,500, you have to file Schedule B and list each payer by name in Part I.4Internal Revenue Service. About Schedule B (Form 1040) Schedule B is also required, even below that dollar threshold, in several other situations:5Internal Revenue Service. 2025 Instructions for Schedule B (Form 1040)
- You received interest as a nominee for someone else.
- You have accrued bond interest or original issue discount that doesn’t match the 1099 as reported.
- You’re excluding Series EE or I savings bond interest used for qualified education expenses.
- You held a financial interest in, or signature authority over, a foreign financial account during the year.
The Part I total from Schedule B flows to Line 2b on your 1040. Tax-exempt interest still goes on Line 2a — it doesn’t appear on Schedule B at all.
What About Interest with No 1099-INT?
You still owe tax on it. The $10 threshold is a reporting rule for the payer, not an exemption for you. A savings account that earned $6 in interest generates no form, but that $6 belongs on your return.1Internal Revenue Service. About Form 1099-INT, Interest Income If you were expecting a form and it never arrived, ask the payer for a duplicate or work from your year-end statements.
Keep the Form Even Though You Don’t Send It
Hold on to your 1099-INTs with your filed return. The IRS asks you to keep records that support your reported income until the statute of limitations closes on that year.6Internal Revenue Service. How Long Should I Keep Records? For most people the practical minimum is three years from the date you filed. It stretches to six years if you left out more than 25% of your gross income, and there’s no limit at all if you didn’t file a return.
Digital or paper doesn’t matter. What matters is being able to pull the form if the IRS ever asks.
Why It Matters That the IRS Already Has a Copy
The IRS runs its copies of information returns through an automated matching program. When what a payer reported doesn’t match what you claimed, you get a CP2000 notice proposing additional tax on the missing income.7Internal Revenue Service. Understanding Your CP2000 Series Notice A CP2000 isn’t an audit; it’s a proposal you can agree with, partly agree with, or dispute by the deadline on the notice. Ignore it and the IRS finalizes the adjustment and bills you.
Interest on any resulting underpayment accrues at 7% per year, compounded daily, as of the first quarter of 2026.8Internal Revenue Service. Interest Rates Remain the Same for the First Quarter of 2026 On top of that, the IRS can assess an accuracy-related penalty of 20% of the underpaid tax if the omission counts as negligence, and the agency specifically cites “not including income on your tax return that was shown in an information return” as an example.9Internal Revenue Service.