Junior ISA calculator
See what saving or investing for a child in a Junior ISA could be worth when they turn 18, based on what's already saved, what everyone pays in each month and the growth you choose.
How the Junior ISA calculator works
Enter your child's age, anything already saved, and the total that you and anyone else will pay in each month. The calculator grows it month by month at the rate you choose, after charges, until the child turns 18, when the Junior ISA becomes theirs to use. Up to £9,000 can be paid in each tax year, which is £750 a month, and the calculator caps payments at that.
What regular saving from birth could grow to
| Monthly payment | Paid in over 18 years | Cash at 3% | Invested at 5%, less 0.3% charges |
|---|---|---|---|
| £25 | £5,400 | £7,120 | £8,370 |
| £50 | £10,800 | £14,241 | £16,741 |
| £100 | £21,600 | £28,482 | £33,482 |
| £250 | £54,000 | £71,204 | £83,704 |
These are illustrations with steady growth. Investments can fall as well as rise, and interest rates on cash change over time. Over 18 years the difference between cash and investing can be large, but so can the swings in an invested account. Some families invest while the child is young and move towards cash as 18 approaches, so a late fall in markets matters less; what suits you depends on how you'd feel about the value dropping.
Junior ISA rules to know
- The child must be under 18 and live in the UK. A parent or guardian opens the account; anyone can pay in.
- A child can have one cash and one stocks and shares Junior ISA, sharing the £9,000 limit. It doesn't use any of your own ISA allowance.
- The money belongs to the child. They can manage the account from 16 and take the money out from 18, when it becomes an adult ISA.
- Money can't be taken out before 18 unless the child is terminally ill or dies.
- Unlike a children's savings account, interest on money from parents isn't caught by the £100 rule, which can make parents pay tax on it.
Our Junior ISA guide explains the rules in full, including Child Trust Funds and the alternative of a pension for your child.
Sources
- GOV.UK: Junior Individual Savings Accounts
- GOV.UK: Junior ISAs, add money to an account
- GOV.UK: Savings for children
- HMRC: Tax-free savings newsletter 19
This calculator gives illustrations based on the figures you enter and the tax rules shown. It isn't personal financial advice. Our guides are general information and education, not personal financial advice. If you are unsure whether an investment is right for you, speak to a regulated financial adviser.
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