Do I need to file a 1040X? How does that affect my state tax return?

April 16, 2012 12:24 AM

Tax panic! I e-filed my 1040 federal return a few weeks ago; then, while finally tackling my state tax return last week, I discovered I'd incorrectly transferred an amount from one of my additional forms into the 1040. Do I need to file a 1040X to correct this, and how do I proceed with my state return?

I transferred the wrong line from Form 8889 into Form 1040, which then basically changed my AGI, taxable income, tax amount, and amount overpaid (my refund would increase a bit, when all is said and done).

The IRS website says that math errors will likely be corrected and wouldn't require a 1040X to be filed, but does this kind of error fall under that category?

And finally: I plan to finish and mail in my state return by Tuesday -- I filled it in with the correct amounts for income etc. But would I need to attach the original 1040, plus the amended 1040+the 1040X... or how would that work, exactly?

posted by estherbester to law & government (4 answers total)

I don't believe that will count as a math error, but it might. I would probably fail on the safe side and file an amended return.

As for the state taxes, if they don't have specific advice for what to do with amended returns, I would file it with a copy of what the 1040 would look like had you not made the mistake.
posted by gjc at 3:02 AM on April 16, 2012 [1 favorite]

I am not an accountant. Had this happened to me, I would fill out the 1040X, fill out the state form with the amended (correct) info, and attach the 1040X to the state return. If you have an increase in your refund, you will not incur penalties from the IRS for the incorrect 1040 filing.
posted by bedhead at 6:45 AM on April 16, 2012

Thanks, you guys! I am going to file a 1040X, and for my state return, attach the amended 1040 with the 1040X along with all my supporting forms.

I'll try to follow up on this when I get my refunds... or if anything else happens (fingers crossed!).
posted by estherbester at 1:00 PM on April 16, 2012

As promised, a follow-up: my bonus refund and regular state tax refund arrived in due time, so I guess filing the 1040X, and then attaching the amended 1040 + 1040X for my state return, was the way to go. Thanks again!
posted by estherbester at 9:55 PM on June 19, 2012