When an electronically filed Individual return is rejected, there is a five calendar day "perfection period" (aka look back period) to correct the return and resubmit it electronically for it to still be considered timely filed. This five day period applies to returns filed on extension as well.
If the taxpayer decides to paper file the rejected return, to be considered timely filed the paper return must be postmarked by the later of the due date of the return, including extensions, or ten calendar days after the date of the last IRS reject as long as
- the first transmission was timely filed, including extensions, and
- The last transmission was made within 10 calendar days of the first transmission.
(The paper filed return should include an explanation of why the return is being filed after the due date, and ideally will include a copy of the IRS's rejection notice.)
Rejected automatic extension applications (Form 4868 or Form 2350) also must be retransmitted within the five calendar day perfection period to be considered timely filed.
When an electronically filed Business return is rejected, there is a ten calendar day "perfection period" to correct the return and resubmit it electronically for it to still be considered timely filed. Rejected extension requests filed on Form 7004 or Form 8868, however, must be resubmitted within five days of the due date in order to be considered timely filed.