Can you pay into a Junior ISA and an adult ISA in the same year?

Q: If I put £3,000 into a Junior ISA for my grandson, can he then put £17,000 into his ISA in the same year when he reaches 18?

A: Many thanks for your question. To cut a longish story short - yes, your grandson would be able to pay £17,000 into his ISA in the same tax year that you have contributed £3,000 into a Junior ISA in his name. The tax year starts on the 6 April.

In fact, you could both contribute higher amounts than this. The current annual Junior ISA allowance is £9,000, so you could pay in up to this level as long as he is under 18. Moreover, your grandson is then able to use the full £20,000 allowance available to adults once he turns 18.

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In other words, it is possible for people turning 18 in the middle of a tax year to contribute a total of £29,000 into tax-efficient ISAs within the same tax year - £9,000 to a Junior ISA before their 18th birthday and a further £20,000 once they turn 18.

Note that their Junior ISA will automatically mature into an adult ISA once they turn 18 and they will be handed full control of the money at that point.

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Important information - investors should note that the views expressed may no longer be current and may have already been acted upon. Eligibility to invest in a Stocks and Shares ISA or Junior ISA and tax treatment depends on personal circumstances and all tax rules may change in the future. Withdrawals from a Junior ISA will not be possible until the child reaches age 18. This information is not a personal recommendation for any particular investment. If you are unsure about the suitability of an investment you should speak to one of Fidelity’s advisers or an authorised financial adviser of your choice.