Prior-year returns and amended returns
Updated: 2026
Sometimes a prior-year return needs to be filed, or a return that was already filed needs to be corrected. These are different situations and require different records.
Prior-year return or amended return
If a return was never filed for a year, the task is usually preparing a prior-year tax return. If a return was already filed but information must be changed, an amended return may be needed, usually using Form 1040-X.
First, identify what actually happened: the return was never filed, was rejected, was accepted by the IRS but contains an error, or a tax document arrived after filing.
Documents needed
Gather the original return if it was filed, all W-2/1099 forms for the year, records for children and dependents, credits, payments, IRS letters, and any documents related to the change.
If several years are involved, separate the documents by tax year before review.
When not to rush
If you just filed and noticed a possible error, it may be necessary to confirm whether the return was accepted, whether all forms have arrived, and whether an amended return is actually needed.
If the IRS has already sent a letter, compare the letter with the return and supporting records before sending a correction.
Security and expectations
Amended and prior-year returns often take more time because the facts of a specific year must be reconstructed. Do not send old returns, SSN, or tax documents through the regular contact form.