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HMRC internal manual

COTAX Manual

Background: company taxation overview: introduction

This section gives a brief explanation of the differences between the CT Pay and File regime and the CT Self Assessment regime.

Complete technical instructions are obtainable in the Company Taxation Manual.

Before the CT Pay and File regime, inspectors raised assessments on the CTA IT system that has now been decommissioned. The COTAX IT system is used to administer most aspects of both the CT Self Assessment and CT Pay and File regimes.

See COM30020 for details of how the two regimes work.