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HMRC internal manual

COTAX Manual

Case records: maintaining case records: introduction

New companies incorporated or registered under the Companies Acts are set up on COTAX automatically using data from Companies House.

CT Services offices set up other taxpayers liable to CT, such as clubs or unincorporated associations.

Changes to designatory data for companies incorporated at Companies House are received directly and the COTAX record updated automatically. When you receive updates for an unincorporated association, you should amend the record as soon as possible. Some amendments can also be made automatically online by a company or agent submitting a structured action request (SAR) updating the company and / or agent’s details.