Visual Studio 2017 and newer
The RDLC Report Designer can be found on the Visual Studio Marketplace:
Besides that, the ReportViewer Control, which is the runtime requirement for showing reports in ASP.NET or Windows Forms Applications, is now available through NuGet. See here for details.
Visual Studio 2015
The Report Designer is part of the Microsoft SQL Server Data Tools.
You can add it using the Visual Studio setup (Programs and Features > Visual Studio 2015 > Change)
