Transmission Information Date Begin Transmitting live IRS e-file returns February 12, 2021 Last date for transmitting timely filed returns May 17, 2021 Last date for transmitting timely filed Forms 4868 May 17, 2021 Last date for retransmitting rejected timely filed returns May 22, 2021 Last date for retransmitting rejected timely filed Forms 4868 May 22, 2021 Last date IRS will accept test transmissions No cut-off date Last date to submit new IRS e-file Applications No cut-off date Transmitting timely filed Forms 4868 or 2350 to meet overseas exception June 15, 2021 Retransmitting rejected timely filed Forms 4868 or 2350 to meet overseas exception June 20, 2021 Last date for transmitting returns on extension from Form 4868 October 15, 2021 Last date for retransmitting rejected late or returns on extension from Form 4868 October 20, 2021
