The following links provide information and technical guidance for Software Developers and Transmitters who are interested in developing software for the Modernized e-File Forms 1120, 1120S, and 1120-F. You will find the XML Schemas, Business Rules and other useful information separated by tax year. Forms 1120, 1120S, and 1120-F Stylesheets can be downloaded for use in displaying XML tax return data. Production & Acceptance Testing System (ATS) - Current Valid Schemas Tax Year Form Type 2021 Form 1120,1120S, and 1120-F 2020 Form 1120, 1120S, and 1120-F 2019 Form 1120, 1120S, and 1120-F 2018 Form 1120, 1120S, and 1120-F Modernized e-File (MeF) Schemas and Business Rules
