1099-B forgot to file

[Darkwild5]

In 2018 I signed up for an account on Robinhood and sold some stocks. I just checked for the 2020 tax info and saw I never sent in the 2018 one. In the forum it says $2,374 for cost basis and to the right grand total net gain/ loss -118.32 ... this is to say I don't think I made anything. I am a bit concerned because I am an honest person and don't want to get in trouble. What do I do?

[Anonymous]

for future reference: many times brokers do not issue all 1099-B's by 1/31.  there may be things on the form that they have to wait to finalize.  in some cases the 1099-B is not issued until 3/15 and I even received a corrected 1099-B in November - well after the latest filing date.

the question becomes whether cost basis was reported to the IRS.    if yes, I would wait for a letter of inquiry, if any, from the IRS.  you got nothing to lose, since the loss would at worst have no effect on 2019 taxes. might even increase your refund. you could also file an amended return, but you have to wait until your return is fully processed before you could do so.

if cost basis is not reported to the IRS, then I would file an amended return

cost basis is reported if the type on the 1099-B is A or D.     

[Darkwild5]

I never attached the forum to my tax returns and I don't think I received any notice from the IRS. Since I was new to trading, I had no idea that everything you make or lose is supposed to be reported. I was under the impression if you gained a large amount of capital you would need to report that. The 1099 B didn't exist until yesterday for me. I had no idea it was a thing nor that I needed to include it in my tax returns. With that said, the cost basis is under A on my forum.