Tax Year 2021 Form 1040 Modernized e-File (MeF) Assurance Testing System (ATS) information is outlined below. If you support these forms, you will need to contact the e-Help Desk for testing. Please monitor this page for any Tax Year 2021 Form 1040 Series and Extensions ATS scenario updates. Tax year 2021 Form 1040 series and extensions MeF ATS scenarios 1040 MeF ATS Scenario 1 PDF (Form 1040) – 11/16/2021 1040 MeF ATS Scenario 1 PDF (Form 1040-NR) - 01/07/2022 1040 MeF ATS Scenario 1 PDF (Form 1040-SP) – 11/16/2021 1040 MeF ATS Scenario 1 PDF (Form 1040-SR) – 11/16/2021 1040 MeF ATS Scenario 2 PDF (Form 1040) - 01/07/2022 1040 MeF ATS Scenario 2 PDF (Form 1040-NR) - 12/06/2021 1040 MeF ATS Scenario 2 PDF (Form 1040-SR (SP)) – 11/16/2021 1040X MeF ATS Scenario 2 PDF (Form 1040-X) – 01/21/2022 1040 MeF ATS Scenario 3 PDF (Form 1040) – 11/16/2021 1040 MeF ATS Scenario 3 PDF (Form 1040-NR) - 12/06/2021 1040X MeF ATS Scenario 3 PDF (Form 1040-X) – 12/10/2021 1040 MeF ATS Scenario 4 PDF (Form 1040) – 11/29/2021 1040 MeF ATS Scenario 4 PDF (Form 1040-NR) - 12/06/2021 1040 MeF ATS Scenario 5 PDF (Form 1040) - 01/07/2022 1040 MeF ATS Scenario 5 PDF (Form 1040-NR) - 12/06/2021 1040 MeF ATS Scenario 6 PDF (Form 1040-SS) – 12/01/2021 1040 MeF ATS Scenario 7 PDF (Form 1040) – 11/16/2021 1040 MeF ATS Scenario 8 PDF (Form 1040) – 11/16/2021 1040 MeF ATS Scenario 9 PDF (Form 1040) – 11/16/2021 1040 MeF ATS Scenario 10 PDF(Form 1040) – 11/16/2021 1040 MeF ATS Scenario 11 PDF(Form 1040) – 11/16/2021 1040 MeF ATS Scenario 12 PDF (Form 4868) - 09/27/2021 1040 MeF ATS Scenario 13 PDF (Form 9465) - 09/27/2021 1040 MeF ATS Scenario 14 PDF (Form 56) – 11/16/2021 1040 MeF ATS Scenario 15A PDF (Form 2350) - 09/27/2021 For information and questions regarding ATS, please contact the e-Help Desk at 866-255-0654. Modernized e-File (MeF) Assurance Testing System (ATS) Updates Page Tax Year 2021 Modernized e-File Schemas and Business Rules for Individual Tax Returns and Extensions