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HMRC internal manual

Company Taxation Manual

Residence: outward company migration: ceasing residence for double taxation agreement purposes

Until 29 November 1993, a UK resident company could, without losing its UK resident status, become a resident of another country for the purpose of the double taxation agreement between the UK and that country by moving its place of effective management to the other country.

This was ‘treaty migration’ and the company was known as a treaty non-resident company. Although the company remained UK resident under domestic law we might have lost the right to tax some income and gains, as in the case of a genuine migration. TCGA92/S186 provided for a charge on certain unrealised chargeable gains or losses of such a company.

From 30 November 1993, S186 was repealed and a treaty migration became an actual migration. It follows that TCGA92/S185 applies instead. See CG42370.