With a submittal of the 1040X amended Income Tax Return do I have to attach the 1099's that I omitted? Do I have to also send the original 1040?

[fivekbob]

My original tax return was already electronically submitted, accepted and processed with Turbo Tax. Since I mail my 1040X, do I have to attach original 1040's and the W2's and 1099's that were listed correctly?

[JohnW15 · Accepted solution]

Don't attach your original return, and only attach 1099-Rs that support changes made on the amended return, but only if tax was withheld on the 1099-Rs. 

The IRS gives instructions in "Assembling Your Return" on page 17 of its Instructions for Form 1040X:

"Don’t attach a copy of your original return, correspondence, or other items unless required to do so.  Attach to the front of Form 1040X:

•A copy of any Form W-2, Form W-2c, or Form 2439, Notice to Shareholder of Undistributed Long-Term Capital Gains, that support changes made on this return;

•A copy of any Form W-2G, Certain Gambling Winnings, or Form 1099-R that support changes made on this return, but only if tax was withheld; and

•A copy of any Form 1042-S, Foreign Person's U.S. Source Income Subject to Withholding; Form SSA-1042S, Social Security Benefit Statement (Nonresident Aliens); Form RRB-1042S, Payments by the Railroad Retirement Board (Nonresident Aliens); or Form 8288-A, Statement of Withholding on Dispositions by Foreign Persons of U.S. Real Property Interests, that support changes made on this return. 

Attach to the back of Form 1040X any Form 8805, Foreign Partner's Information Statement of Section 1446 Withholding Tax, that supports changes made on this return."

[Bolding mine.]