The links below provide information and technical guidance for Software Developers and Transmitters who are interested in developing software for the Modernized e-File (MeF) Form 8849 for Tax Year (TY) 2020. Included are the XML Schemas, Business Rules, Release Memorandum and specific instructions. Developers and other Authorized IRS e-file Providers can find information on e-filing returns through MeF in the Publication 4163 and Publication 4164. Test Scenarios for Form 8849 can be found on the Modernized e-File (MeF) Assurance Testing System (ATS) Page. XML Schemas, Business Rules and Release Memos - Throughout the year, multiple versions of these documents may be in use at the same time. Special attention should be paid to the Release Memo issue date and the projected start and end dates for Assurance Testing System (ATS) and Production. Tax Year 2020 Documents Tax Year 2020 8849 MeF Accepted Forms and Schedules Tax Year 2020 8849 MeF Return Due Dates Tax Year 2020 Stylesheets: MeF Stylesheets Tax Year 2020 Known Issues and Solutions – Revised 08/27/2021 TY2020 Valid XML Schemas and Business Rules for Form 8849 Modernized e-File Version Available Date ATS Date Production Date Comments 2020v1.1 07/23/2019 Start: 11/04/2019 End: TBD Start: 01/07/2020 End: TBD Business Rules Change Page dated 07/22/2020 Business Rules Change Page dated 09/03/2019 Business Rules Change Page dated 09/02/2021 2020v1.0 06/11/2019 Not Valid for ATS Not Valid for Production N/A Current Valid XML Schemas and Business Rules for Form 8849 Modernized e-File (MeF) Schemas and Business Rules
