Ok so discovered the name of the file is not needed in the url. From Jasper Server, when you navigate to reports, then right click report to get its properties, there it wil show the path e.g /reports/folder/ReportName I just use this as the end of the url e.g http://localhost:8080/jasperserver/rest_v2/reports/reports/folder/ReportName If you now want said report back in PDF or CSV just add that extension.... http://localhost:8080/jasperserver/rest_v2/reports/reports/folder/ReportName.pdf URL Query Params also work, these have to be created both as parameters in the report, which are used in the SQL query, and also taken in as a Controls & Resources input control params on the server side. You can do this by editing the report within the server,
