Get your taxes done using TurboTax

Since the 1099-INT is issued in your name and SSN, the IRS doesn't know that your sister is on the joint account.  They only know a Form 1099-INT was issued to you for the amount of your interest. You can also split the interest. Save any records with your tax paperwork, just in case it gets questioned, you will be able to show that she was also on the account and how you split the interest.

In general, the IRS treats interest earned on a joint bank account as income, and all account owners are liable for taxes on their portion of the interest earned. 

To enter it in TurboTax:

1. After you enter the Form 1099-INT, your next screen will say, "Did any of these uncommon situations apply?"
2. You would select "I need to adjust the interest reported on my form."
3. Select "Continue"
4. On your next screen you will see "Tell us about your interest adjustment"
5. Enter the amount you adjusted your 1099-INT by
6. Select the drop-down for reasons for adjustment 
7. Select "I received all or part of this interest for someone else (I am a nominee).

Your TurboTax screen will look something like this:

Click here for: Instructions for Forms 1099-INT and 1099-OID (01/2024)

Click here for information on entering a Form 1099-INT.