I am an agent and don't currently submit my client's Company Tax Returns online. What do I need to do to get started?
If you're registered with HM Revenue and Customs (HMRC) as an agent and you have an Agent Reference Number, you can register for Corporation Tax for Agents . You can register as an agent by contacting your Corporation Tax Office.
You can then register and enrol for Corporation Tax for Agents through the online services registration pages.