The tables below provide links to the Tax Year 2021 Extensible Markup Language (XML) Schemas, Business Rules, and Release Memorandum for the Employment Tax Forms (Form 94x series). Throughout the year, multiple versions of Schemas and Business Rules may be in use at the same time. The table reflects the effective dates in the Assurance Testing System (ATS) and Production System, for each version. Tax Year 2021 Documents Tax Year 2021 94x MeF Accepted Forms and SchedulesPDF Tax Year 2021 94x MeF ATS Information Tax Year 2021 94x MeF Forms and Attachment ListXLSX Tax Year 2021 94x MeF Return Due DatesPDF Tax Year 2021 94x MeF Stylesheets Tax Year 2021 Known Issues and SolutionsXLSX - Revised 06/29/2022 Tax Year 2021 Form 94x (Annual Forms) Version Available Date ATS Dates Production Dates 2021v2.0 10/14/2021 Start: 11/21/2021 End: TBD Start: 01/07/2022 End: TBD 2021v1.0 09/04/2021 Start: 10/12/2021 End: 11/20/2021 Not Valid for Production Tax Year 2021 Form 941x (Quarterly Forms) Version Available Date ATS Dates Production Dates 2021v3.0 05/29/2021 Start: 06/20/2021 End: TBD Start: 07/01/2021 End: TBD 94x On-Line Signature PIN Registration Application Version Available Date ATS Dates Production Dates CUv3.0 05/17/2018 Start: 10/29/2018 End: TBD Start: 01/08/2019 End: TBD Form 9465 Version Available Date ATS Dates Production Dates CUv24.1 02/10/2022 Start: 03/06/2022 End: TBD Start: 03/20/2022 End: TBD CUv24.0 10/17/2020 Start: 11/22/2020 End: TBD Start: 02/12/2021 End: TBD Schemas and Business Rules for Employment Tax Modernized e-File (MeF) FormsModernized e-File (MeF) Program Information
