Mistake on income

It depends.  You will likely need to amend your return. 

IRS may or may not catch the error, depending on what it is, but it could take quite a while (sometimes more than a year.) 

If it decreases your refund from what you originally filed, you could owe interest and/or penalties on the difference and these would increase as time goes on.

Be sure to wait until your return is Accepted or Rejected before amending.  Also, please note that Form 1040X needed to amend your Federal Return is not expected to be available until 2/12/2020.

Here are the instructions to amend your tax return:

If it is rejected, you can log back in to your TurboTax and make the correction.  No Amended Return required.  

If it is accepted and contains incorrect information, you can amend the return    

To Amend your return in Turbo Tax Online follow these steps:

1.  Sign in to your Turbo Tax Account

2.  Scroll down to  Your tax returns and documents and select Amend (change) 2019 return, then Amend using Turbo Tax Online.

3.  Select the reason you are amending and Continue

4.  Answer the questions about your Federal return, (there may be no changes) then begin amending your State return when it says "Lets get started on your state taxes...."

To Amend your return in Turbo Tax Desktop;

1.  Open your tax file you need to amend and select Online and Check for Updates.  

2.  Go to the Federal Taxes tab (or the Personal Tab, if you are using Home & Business) and select the Other Tax Situations Tab.

3.  Scroll down to Other Tax Forms and Select Start next to Amend a return.

4.  Answer the appropriate questions for the State and Federal Returns.  

Here is a great article that goes into more detail regarding the steps.

Amending my State Return

Please note, amended returns need to be printed and mailed and It does take up to 12-16 weeks for more for Amended returns to be processed.