If you need to submit certain forms (or attachments) with your return, you are still able to e-file. However, you will need to complete and mail in Form 8453 U.S. Individual Income Tax Transmittal for an IRS e-file Return along with the forms or attachments.
Any documentation required for these forms should also be attached. If you need to attach other forms, statements, or declarations to your Form 1040, you will need to paper-file your return as the IRS will not accept them electronically or with Form 8453.
Do not send Form W-2 to the IRS with Form 8453, keep it for your records. You will only need to send Form W-2 with the return if you are paper-filing.
Form 8453 (with the required forms or supporting documents) must be mailed to the IRS within three business days after receiving acknowledgement that the return was accepted. An electronically-transmitted return will not be considered complete until a Form 8453 is received by the IRS.
Mail Form 8453 to:
Internal Revenue Service
Attn: Shipping and Receiving, 0254
Receipt and Control Branch
Austin, TX 73344-0254
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the webpage or document at the time it is accessed.