You'll need to amend your return to include the K1.
To avoid unnecessary delays, do not amend until your original return has been fully processed.
You can e-file your 2020 amended federal tax return, but most states require amendments to be printed and filed by mail.
Allow 16 weeks for processing.
See this TurboTax FAQ for help with amending.
You can check the status of your amended return here, but allow 3 weeks after filing for it to show up.
**Mark the post that answers your question by clicking on "Mark as Best Answer"
I'm in the same position. I already filed my returns and they have been accepted and i've received my returns. Now I am starting to receive K1's from different investment purchases. I'm assuming I will need to file an amended return? How long can I wait to amend, so that I'm sure I've received all the K1's I'll be getting to avoid having to amend a 2nd time?
TurboTax expects to be able to begin filing amended tax returns on March 25th.
This date is subject to change, especially due to the recently passed American Rescue Plan.
You currently have until April 15 to file your amended tax return and pay any additional tax due to avoid penalty.