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) 2023. Included are the Extensible Markup Language (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 Modernized e-File (MeF) in the Publication 4163 PDF and Publication 4164 PDF. Test Scenarios for Form 8849 can be found on the Assurance Testing System (ATS). XML Schemas, Business Rules, and Release Memo – 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 2023 documents Tax Year 2023 8849 MeF Accepted Forms and Schedules PDF Tax Year 2023 8849 MeF Return Due Dates PDF Tax Year 2023 Stylesheets: MeF Stylesheets Tax Year 2023 Known Issues and Solutions XLSX – Revised 7/1/2024 TY2023 valid XML schemas and business rules for Form 8849 Modernized e-File Version Available date ATS date Production date Comments 2023v1.1 11/18/2022 Start: 12/18/2022 End: TBD Start: 01/12/2023 End: TBD Business Rule Updates dated 11/13/2023 2023v1.0 06/09/2022 Start: 10/24/2022 End: TBD Start: 01/12/2023 End: TBD N/A Valid XML schemas and business rules for Form 8849 Modernized e-File (MeF) schemas and business rules