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HMRC internal manual

International Manual

How the corporate tax regime works for Controlled Foreign Companies: Controlled Foreign Company supplementary pages

The requirements to include details of controlled foreign companies on tax returns have been kept as simple as possible in order to minimise compliance costs. Those details that are required must be included on supplementary pages to the corporation tax self assessment return. Companies that need to complete these supplementary pages should put a cross in the appropriate box on the front of the return and attach the supplementary pages CT600B (reproduced at INTM256640), which is available from the HMRC website.

The flowchart at INTM256850 - “what should be included in the corporation tax self assessment return?” - may be helpful here.