For UK tax purposes gift of cash are not subject to income or capital gain tax provided the money is brought to the UK in the correct way but there are potentially income, capital gains and inheritance tax aspects to consider when bringing cash gifts to the UK.
The gifts are potentially subject to UK inheritance tax as potentially exempt transfers (PETs) but only if the persons making the gifts do not survive 7 years of the gift. If your your father and/or partner's mother are domiciled in the UK (i.e. permanent and habitual home is in the UK) then the PET cannot be avoided. Where they are not domiciled in the UK the gifts should be structured in the following way to avoid incurring a PET.
To avoid complications caused by mixing the gifts with other accounts you should therefore:
1. Open a new non-UK bank account (or use an unused one)
2. Relatives pay into this account
3. Then you transfer the money to the UK
This method also prevents other complications for income and capital gains tax caused by mixing the gifts with other sources of income.
This treatment applies regardless of the amounts involved.
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