Credit union “dividends” are usually actually interest from saving accounts, checking accounts, or CDs, and are generally reported as interest in Box 1 of Form 1099-INT, when the form is required to be provided to the taxpayer.
You’ll want to enter this income as interest in TurboTax Online:
Enter all of your information. Although the screens reference Form 1099-INT, no form is needed. Just enter the information that you have.
[Amended 2/24/2023 | 1:54 pm PST]
Are you sure?
....the Credit Union calls them dividends...but if they from the CU savings/checking accounts or CDs, they are usually reported just as "interest" on a 1099-INT form, in box 1.
I get a 1099-INT form from my credit union every year for my CU "dividends"....(well, because they are over $10), but even if under that amount I would report them myself as a 1099-INT (as long as it was 50cents or higher).
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Now, if the CU happens to have actual stock offerings...beyond savings accounts...those stock dividends would be on a 1099-DIV.