A UK resident is normally taxed on the ‘arising’ basis, which means that all worldwide income and gains will be taxed in the UK, even if foreign income and gains have been taxed in another country.
Often, when this does happen, relief will be given in the UK for the foreign tax suffered. The relief will be through a double-taxation treaty or unilateral relief.
When people come to the UK to work, they can end up being UK resident, but not UK domiciled, and then different rules will apply.
A person who is UK resident but not UK domiciled can choose whether to be taxed on the arising basis or the remittance basis.
If an individual chooses the remittance basis, they will then pay UK tax on all income and gains arising in the UK, plus any income or gains arising outside of the UK, but remitted to the UK.
If an individual chooses the remittance basis, he or she may also be liable to the RBC. This charge is payable in addition to any UK tax due on the foreign income or gains remitted to the UK, and tax due on UK income and gains.
The RBC will be due when the remittance basis is chosen and the individual has been resident in the UK for seven out of the previous nine UK tax years, and has overseas income or gains totalling more than £2,000 in the tax year.
The RBC is £30,000 if the individual has been resident for seven out of the last nine years. However, if the residence has been for 12 out of the preceding 14 UK tax years, the RBC will be £50,000.