If couple is registered as foster carer and wife as a main carer, do we need to split their income between 50/50 in couple ? In that case, do we need to divide annual tax exemption of £10,000 and tax relief after every child between couple equally? Since last 5 years, foster carer's income had been declared under wife's name. If allowed as mentioned earlier, from this tax year, can we split income and tax exemption and tax relief from current year as it will be different from the past years submission?