Over contributed to 401k by $4

You must include the excess deferral in your wages in the year the excess deferral happened. 

Please follow the steps below:

1. Login to your TurboTax Account 
2. Click "Wages & Income" (under Federal) on the left side of your screen
3. Scroll  down to "Less Common Income" and click "Show More"
4. Scroll down to "Miscellaneous Income, 1099-A, 1099-C" and click "Start"
5. Select "Other income not already reported on a Form W-2 or Form 1099" and click "Start"
6. On the "Did you receive any other wages?" screen answer "Yes" and click "Continue"
7. Continue until you get to the "Any other earned income" screen, answer "Yes" and click "Continue"
8. On the "Enter Source of Other Earned income" screen select "Other" and click "Continue"
9. On the "Any Other Earned Income" screen enter "2024 Excess 401(k) Deferrals" for the description, enter the amount and click "Done".

I assume you didn't have any earnings on this small amount and therefore this is all you need to do.

I realized when re-reading my post, I might not have been clear on my end.

I over contributed the 401k for 2024. The 401k plan sent me a check for $4 this January (2025).

And then, I'm assuming if I do this, I won't have to report it again for 2025 tax season, correct?

Sorry! Just want to make sure I'm doing the right thing.

Thank you!

Yes, all you need to do is to you report the excess with the steps mentioned above. You don't have to report anything on your 2025 return since you didn't have any earnings.

"You must include the excess deferral in your income for the year of the deferral." (IRS)

"Any income on the excess deferral taken out is taxable in the tax year in which you take it out." (IRS)