I’ve looked online and asked AI this question but I get conflicting responses.
My son filed his taxes but his income was below the threshold required to file. Because he sold some appreciated stock, his taxes reflected a payment due.
Can he undo filing since it was not necessary? Some sources claim it was necessary due to the 1099B while others have stated it was not necessary even with the 1099B
Are you sure he was below the threshold? How old is your son, did you provide more than half of his support for 2025, and was he a full-time student during 2025? All of those things can affect the requirement to file taxes.
Sorry, once taxes are filed, you can’t unfile them. He could amend his return, but if he tries to take the 1099-B off of his filed taxes, the IRS will question that, because they got the 1099-B, too.
AJ
FT student, income was 13k, but has ST and LTCG from investment sales. From what I have read, a 1099b requires one to file.
Even if he didn’t get a 1099-B, it’s likely that with non-earned income (like investment gains, interest, etc.), he would have had to file. Presuming that $13k is not at least 50% of his expenses for 2025 (including, but not limited to: rent (equivalent if living at home), food, tuition, books, transportation, etc.), he is your dependent. The standard deduction for dependents in 2025 is the greater of $1350 or their earned income plus $450. It is NOT the standard deduction for single filers. Since he had more than $1350 in total income, if at least $450 was realized net total gains (ST and LT) or other non-earned income, he would owe tax at least on his ST gains, unless he had a carryover loss from a prior year.
If he doesn’t want to pay anything in future years, you can advise him to only realize LT gains, and to avoid other ordinary income, like interest, or to realize less than $450 in non-earned income. He may still have to file, but at least he wouldn’t have to make a payment.
Edited to add: Just to be clear - it’s very difficult for dependents to actually be “below the threshold” unless they have ONLY earned income. So your son wasn’t actually below the threshold, as long as he was your dependent.
AJ
Got into a similar situation once and it’s way less flexible than people expect. After a return is submitted, there’s really no “undo” button, you’re basically locked into fixing it through changes instead of removing it entirely. The part about investment income makes it even trickier since that data is already reported. Best move is just follow the proper amended return process and clean it up from there.