The tables below provide links to the Tax Year 2020 Release Memorandum, XML Schemas, and Business Rules for the MeF 1040 Series and Extensions. Throughout the year, multiple versions of Business Rules and Schemas may be in use at the same time. For each version, the tables below reflect the effective dates in the Assurance Testing System (ATS) and Production System. Tax Year 2020 Documents Tax Year 2020 Accepted Forms and Schedules for Individual Tax Returns and Extensions XLSX Tax Year 2020 Form 1040 Series Forms and Attachments List XLSX Tax Year 2020 Recommended Names for Portable Document Files (PDFs) Attached to 1040 MeF Submissions XLSX Tax Year 2020 Known Issues and Solutions XLSX Tax Year 2020 Form 1040 Series Version Date Available ATS Date Production Date Comments 2020v5.3 10/12/2021 10/12/2021 01/24/2022 10/12/2021: 1040 Series Schema Only 2020v5.2 07/26/2021 Not Valid in ATS Not Valid in Production 07/26/2021: 1040 Series schema only. 2020v5.1 06/23/2021 06/13/2021 06/20/2021 6/23/2021: 1040/1040-NR Change pages only. 2020v5.1 02/09/2021 03/07/2021 03/21/2021 2020v5.0 **11/23/2020 12/13/2020 02/12/2021 01/07/2021: 1040 and 1040-SS/PR Change pages only. **01/07/2021: 1040-NR Business Rule Set provided in this delivery supersede the 1040-NR Business Rule Set provided on 11/23/2020. 12/14/2020: 1040 and 1040NR Business Rule Change Pages ONLY were made available on 12/14/2020. 12/14/2020: 1040 and 1040NR Business Rule Change pages will be operational in 1040 Series and Extensions ATS on 12/20/2020. 2020v4.0 10/17/2020 11/22/2020 Not Valid in Production 2020v3.0 09/02/2020 11/02/2020 Not Valid in Production 2020v2.0 07/22/2020 Not Valid in ATS Not Valid in Production 2020v1.0 06/15/2020 Not Valid in ATS Not Valid in Production Tax Year 2020 Form 4868 Version Date Available ATS Date Production Date Comments 2020v3.0 10/17/2020 11/22/2020 02/12/2021 2020v2.0 07/22/2020 11/02/2020 Not Valid in Production 2020v1.0 06/15/2020 Not Valid in ATS Not Valid in Production Tax Year 2020 Form 2350 Version Date Available ATS Date Production Date Comments 2020v3.0 10/17/2020 11/22/2020 02/12/2021 2020v2.0 07/22/2020 11/02/2020 Not Valid in Production 2020v1.0 06/15/2020 Not Valid in ATS Not Valid in Production Form 9465 Version Date Available ATS Date Production Date Comments CUv24.0 10/17/2020 11/22/2020 02/12/2021 CUv23.0 09/02/2020 11/02/2020 Not Valid in Production CUv22.0 07/22/2020 Not Valid in ATS Not Valid in Production Form 56 Version Date Available ATS Date Production Date Comments CUv21.0 10/17/2020 11/22/2020 02/12/2021 CUv20.0 07/22/2020 11/02/2020 Not Valid in Production