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?