The following links provide information and technical guidance for software developers and transmitters who are interested in developing software for the Modernized e-File (MeF) Form 8849.
You will find by tax year, the Extensible Markup Language (XML) schemas, business rules, and other useful information and documents. Test scenarios for all valid tax years are posted on the Modernized e-File (MeF) Assurance Testing System (ATS) page.
Form 8849 stylesheets can be downloaded for use in displaying XML tax return data.