Here's another way --
You must have a copy of the original tax return you want to update.
The simplest way is to prepare your correct tax return (using TurboTax for example, or other means) and print it.
Then lay the paper printouts of both returns (correct and original) side-by-side.
You now have all the information needed to prepare Form1040X by hand.
It's pretty straight-forward.
The blank form in fillable PDF format and its instructions are available at www.irs.gov.
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How to file --
Do not include your old 1040 nor your revised 1040 because the Form 1040X reflects any changes there and becomes your new tax return.
Include any new/corrected document only if it shows federal tax withheld, and include in order only those Sequence Numbered tax forms and Schedules that changed or were added due to your amendment.
Attachment Sequence Number is on all the forms and Schedules that come after 1040.
Mail to the address shown for your location in the Instructions for Form 1040X.
