I forgot to file W-2G form after I'd done my tax file. what can I do now? tks.

[AndreaC1]

If this is a W-2G from 2017 and you have already e-filed, you will need to wait until the IRS has accepted or rejected the return before and amend it. There is no way to add it before the IRS has accepted or rejected it. 

• If they accept, you will need to wait until the return is processed and you have received your refund and then amend. If you owe them, pay them first and then amend. 
• If they reject, you can add the W-2G that you have and re-submit the return. 

Once the 2017 amend option is available, 2017 will become a clickable link below. You can then click it for instructions on how to amend the return. 

And you'll find steps on how to add that W-2G here How do I enter a W-2G? when you are ready to amend.

How to amend (change or correct) a return you already filed

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