Author Topic: Forgot Form 8606, do I need to amend my 1040?  (Read 689 times)

MrGreen

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Forgot Form 8606, do I need to amend my 1040?
« on: December 26, 2024, 09:52:06 PM »
I think the answer is no but....

I forgot to fill out Form 8606 when completing my 2023 taxes to document a Roth conversion. I did, however, note the amount of the conversion on our 1040 on line 4b. So we paid the proper amount of taxes. I only noticed my omission as I started looking at 2024's tax forms and the instructions for Form 8606 referring to prior year's 8606s to make some calculations. I have generated the missing 8606 for 2023 so that I have it in my records and can properly calculate basis but I'm unsure if I need to file an amended 1040 for 2023. I wouldn't be changing a single number on my 1040, only attaching the missing 8606, so I question whether this is necessary. The instructions for 1040-X all refer to correcting wrong numbers and recalculating taxes. Further, the IRA already has the 5498s reported by Vanguard so they already have the information.

I'm thinking I can just keep the 8606 on record for myself so that I can make future calculation properly and not mess with a 1040-X. Any experts here have a more informed opinion?

MDM

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Re: Forgot Form 8606, do I need to amend my 1040?
« Reply #1 on: December 27, 2024, 09:43:59 AM »
I forgot to fill out Form 8606 when completing my 2023 taxes to document a Roth conversion. I did, however, note the amount of the conversion on our 1040 on line 4b.
Are you saying that the only nonzero entries on your 2023 form would be lines 16 and 18, with the same number on both lines?

MrGreen

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Re: Forgot Form 8606, do I need to amend my 1040?
« Reply #2 on: December 27, 2024, 11:58:45 AM »
I forgot to fill out Form 8606 when completing my 2023 taxes to document a Roth conversion. I did, however, note the amount of the conversion on our 1040 on line 4b.
Are you saying that the only nonzero entries on your 2023 form would be lines 16 and 18, with the same number on both lines?
Yes

MDM

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Re: Forgot Form 8606, do I need to amend my 1040?
« Reply #3 on: December 27, 2024, 12:14:14 PM »
I forgot to fill out Form 8606 when completing my 2023 taxes to document a Roth conversion. I did, however, note the amount of the conversion on our 1040 on line 4b.
Are you saying that the only nonzero entries on your 2023 form would be lines 16 and 18, with the same number on both lines?
Yes
Then, based on a "what is reasonable" perspective, it makes sense not to amend.  You haven't underpaid, so there would be no point for the IRS to pursue receiving another piece of paper.

Can't guarantee the IRS won't pursue that paper, but it seems "highly unlikely". :)


secondcor521

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Re: Forgot Form 8606, do I need to amend my 1040?
« Reply #4 on: December 27, 2024, 12:51:43 PM »
I agree it's not necessary to file it.

But if you wanted to, you could file the Form 8606 as a standalone return.  It is one of a few tax forms that can be filed independently of the main return.  You just need to sign and date it at the bottom like you would a 1040, and you might need to mail it to a different address than usual.  See the Form 8606 instructions.

But just keeping a copy with your own records is probably fine, because you'll probably file another 8606 in the next year or two assuming you'll continue Roth conversions.

MrGreen

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Re: Forgot Form 8606, do I need to amend my 1040?
« Reply #5 on: December 27, 2024, 02:29:35 PM »
I agree it's not necessary to file it.

But if you wanted to, you could file the Form 8606 as a standalone return.  It is one of a few tax forms that can be filed independently of the main return.  You just need to sign and date it at the bottom like you would a 1040, and you might need to mail it to a different address than usual.  See the Form 8606 instructions.

But just keeping a copy with your own records is probably fine, because you'll probably file another 8606 in the next year or two assuming you'll continue Roth conversions.
Yes, we need to file an 8606 for both myself and my wife this year. This is what led me to realize my omission. I started filling it out and it prompt you to look at the last 8606 for some of the values and that's when I realized the oops.

I also uncovered another oops on my wife's 2022 8606 where I accidentally filled in the wrong value for Roth IRA contribution basis. In early 2019, we recharacterized a $2,400 tIRA contribution made in 2018. You have to calculate the gain or loss at current market value to determine the number to recharacterize so the 1099-R from Vanguard shows $2,334 (a slight loss). The basis is still considered $2,400 for the Roth IRA contribution though. I included the proper note, per 8606 instructions, when we filed our 2018 taxes in 2019 so all that is correct but the next time I filed an 8606 for my wife in 2022 I mistakenly used the $2,334 figure as our Roth IRA contribution basis instead of $2,400. Probably not worth the hassle to correct over $66 but then there will be this discrepancy between my spreadsheets where I keep track of our Roth conversion pipeline and the 8606s we file every year moving forward. I'm thinking I could just mail the 2022 8606 by itself along with a note and that would probably be sufficient for me to start working with the correct $2,400 figure in our taxes moving forward. We already took a distribution from her Roth IRA that wipes out that contribution basis but then it carries over into conversion basis so I'd be dealing with that $66 error for the rest of our lives. Yuck.

MDM

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Re: Forgot Form 8606, do I need to amend my 1040?
« Reply #6 on: December 27, 2024, 02:38:18 PM »
...there will be this discrepancy between my spreadsheets where I keep track of our Roth conversion pipeline and the 8606s we file every year moving forward.
Or just subtract $66 from basis in the appropriate spreadsheet cell and add a note, "unintentional contribution to the coffers of the IRS" and then everything will be in sync. ;)

secondcor521

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Re: Forgot Form 8606, do I need to amend my 1040?
« Reply #7 on: December 27, 2024, 04:51:39 PM »
Or just start using the correct numbers on her next 8606 and the IRS probably won't notice or care.

It's my distinct impression the IRS should try to track all this 8606 stuff but that they in fact do not do so very well if at all.  Other than perhaps some sanity checking on the numbers.

MDM's suggestion is the more conservative one tax-wise.  I.e., less likely to arouse IRS interest.