Thank you for your reply.
I am not sure how you have been reporting your foreign income in the past.
If you are non-domiciled in the UK for tax purposes, then you don't pay UK tax on your forign income or gains if they are less than £2,000 in the tax year and you don't bring them into the UK.
The rules are different if the income is in excess of £2,000.
Furthermore, you can declare the income and pay UK tax and claim foreign tax credit relief against any tax suffered in South Africa on that income/gain or opt for paying tax on remittance basis.
More information on this can be found here
You may find it is a cheaper option to declare income and gains on arising basis (what you receive/made in the tax year) and pay tax on it in the tax year than to pay tax on remittance basis.
You are advised to consider the above before exercising your option.
I hope this is helpful and answers your question.
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