Who reports the interest, and how it gets split

The bank reports interest earned on a joint savings account to the IRS on a Form 1099-INT. That form goes to whoever the account is registered under — usually the first owner listed. But that does not mean that person pays tax on all of it. You and your co-owner can split the interest any way you actually own the account, and you each report your share on your own tax return.

If you own the account 50-50, you each report 50 percent of the interest. If one person owns 70 percent and the other owns 30 percent, the split follows that. The IRS does not care how the bank reported it — what matters is the actual ownership split between you. You will need to decide this before tax time and stick with it year to year unless the ownership actually changes.

The bank will only send one 1099-INT to one person's name and Social Security number. That person receives the form in the mail, but they do not automatically owe tax on all of it. The co-owner needs to report their share even though they did not receive a 1099-INT directly.

Key Takeaways

  • The bank sends the 1099-INT to one owner, but you split the interest based on your actual ownership percentage, not how the form was addressed.
  • Each owner reports their share of the interest on their own tax return, using Schedule B if the interest is over $1,500 for the year.
  • You must agree on the ownership split before filing and keep records showing how you divided the interest.
  • If you disagree on ownership, the IRS may require both of you to file amended returns or may assess the full amount to whoever received the 1099-INT.

How to report your share on Schedule B

Interest under $1,500 for the year goes directly on Form 1040, line 2b (or the equivalent line on your state return). You do not need to file anything extra. Just write in your share of the total interest the bank reported.

If your interest is $1,500 or more, you must file Schedule B (Form 1040), Part I. This is a separate form that lists all your interest income by source. You will write in the account name, the amount of interest you received (or your share of it), and whether you received a 1099-INT. If you did not receive the 1099-INT directly because it went to your co-owner, note that on the form.

The co-owner does the same thing on their own return. If the account earned $800 in interest and you own it 60-40, you report $480 and your co-owner reports $320. You each file your own return with your own share.

What to do if the 1099-INT shows the wrong name or amount

If the bank sent the 1099-INT to the wrong person entirely, or if the amount is wrong, contact the bank and ask them to issue a corrected form. The bank can send a corrected 1099-INT (marked as a correction) to both you and the IRS. This takes a few weeks, so do it as soon as you notice the error.

If the bank will not correct it, you can still file your return with the correct amount on your side. Include a note with your return explaining that the 1099-INT was issued to your co-owner but you are reporting your actual share. Keep a copy of your bank statements showing the interest earned and your ownership agreement or documentation proving your split.

Your co-owner should do the same — report their share and note that the 1099-INT was issued in their name but they are splitting it with you. Both of you reporting your correct shares, even if they do not match the 1099-INT exactly, is cleaner than one person reporting all of it.

Keeping records of your ownership split

Write down how you and your co-owner agreed to split the account. This can be as simple as a note that says "John and Sarah own this account 50-50" or a more formal agreement if you prefer. Keep this with your tax records. If the IRS ever questions why your 1099-INT does not match what you reported, you need to show them the agreement.

Also keep your bank statements for the year. They show the total interest earned and confirm that you both had access to the account. If there is ever a dispute between you and your co-owner about who owns what, the bank statements and your written agreement are your proof.

If your ownership split changes — for example, one person buys out the other's share — document that change too. Going forward, you report based on the new split. The old split applies only to the interest earned while that ownership was in place.

What happens if you and your co-owner disagree on the split

If you and your co-owner cannot agree on how to split the interest, the IRS will likely hold the person who received the 1099-INT responsible for the full amount. That person can then file an amended return later if you reach an agreement, but in the meantime, they carry the tax liability.

This is why it is important to decide the split before you file. If you are opening a joint account with someone, discuss ownership percentages upfront. If you already have a joint account and never discussed it, have that conversation now and document it in writing.

If the dispute is serious — for example, you and a spouse are divorcing — you may need a lawyer or mediator to settle the ownership question. The IRS will not referee ownership disputes; they will just tax whoever the 1099-INT went to unless you both file consistent returns showing a different split.

State tax reporting for joint accounts

Most states follow federal rules: you report your share of the interest on your state return the same way you reported it federally. If you reported $300 in interest on your federal return, you report $300 on your state return (assuming you live in a state with income tax).

Some states have different rules for spouses in community property states (Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington, and Wisconsin). In those states, interest earned during marriage on a joint account may be considered community property, meaning you split it 50-50 regardless of how the account is titled. Check your state's tax authority website or ask a tax preparer if you live in one of these states and are married.

Frequently Asked Questions

Do I have to report interest if I only own a small percentage of the account?

Yes. If you own any percentage of the account, you report your share of the interest, even if it is only $10 or $20. The IRS does not have a minimum threshold for reporting interest income on a joint account.

What if my co-owner refuses to agree on how to split the interest?

The person who received the 1099-INT is responsible for reporting the full amount unless you both file returns showing a different split. If you cannot agree, consider consulting a tax preparer or attorney, especially if the account holds a large balance or the interest is substantial.

Can I change how I split the interest from one year to the next?

Only if your actual ownership of the account changed. If you owned it 50-50 last year and still own it 50-50 this year, you report 50-50 both years. If one owner bought out the other's share mid-year, you split the interest based on who owned what during each part of the year.

Do I need to file Schedule B if my share is under $1,500?

No. Interest under $1,500 goes directly on line 2b of Form 1040. You only file Schedule B if your total interest income (from all sources) is $1,500 or more for the year.

What if the bank issued a 1099-INT to the wrong person entirely?

Ask the bank to issue a corrected 1099-INT. If they will not, the person who received it should report their actual share (not the full amount), and you should report your share on your own return. Include a note explaining the situation and keep your bank statements as proof.