A Junior ISA is a tax-free savings and investment account for under-18s, with an annual allowance of £9,000 in 2026. A parent or guardian opens it, but anyone can pay in. The money is locked away until the child turns 18, when it automatically becomes their own adult ISA.
The short answer
- A Junior ISA is a tax-free account for under-18s, with a £9,000 allowance in 2026.
- It comes in two forms, cash and stocks and shares, and a child can hold one of each.
- Only a parent or guardian can open one, but anyone can pay in up to the annual limit.
A Junior ISA, or JISA, is a long-term, tax-free account designed to help families build a pot of money for a child’s adulthood. Every penny of interest, dividends and growth inside it is free of UK tax, and the allowance is generous, up to £9,000 can be paid in during the 2026 tax year. The trade-off is that the money is genuinely the child’s: it is locked away until their eighteenth birthday, at which point it becomes theirs to do with as they wish.
The two types of Junior ISA
There are two kinds, and a child can hold one of each at the same time. A cash Junior ISA works like a tax-free children’s savings account, paying interest with no risk to the capital. A stocks and shares Junior ISA invests in funds, shares and bonds, aiming for higher growth over the long run in exchange for accepting that the value can rise and fall along the way. Because a Junior ISA typically has a very long time horizon, potentially eighteen years, many families lean towards the stocks and shares version, where that long runway gives investments room to ride out the ups and downs. Our guide to investing for children weighs the choice in detail, and if you are new to markets our beginner’s guide to investing is a good place to start.
The Junior ISA at a glance (2026)
| Feature | Detail |
|---|---|
| Annual allowance | £9,000 per child, per tax year |
| Who it is for | Any UK-resident child under 18 |
| Tax treatment | No tax on interest, dividends or growth |
| Access | Locked until the child turns 18 |
| Types | Cash JISA and stocks and shares JISA |
| At age 18 | Automatically becomes an adult ISA |
The £9,000 allowance is separate from your own £20,000 adult ISA allowance, so funding a child’s JISA does not eat into your personal tax-free investing. It cannot be carried forward, though, if a given year’s allowance is not used, it is simply lost when the tax year ends on 5 April.
Who can open one and pay in
Only a person with parental responsibility, usually a parent or legal guardian, can open a Junior ISA and act as the registered contact. But once it is open, anyone can contribute: grandparents, aunts, uncles, godparents and family friends can all pay in, up to the shared £9,000 annual limit. This makes a JISA a natural home for birthday and Christmas money, and a popular way for grandparents to help, a route we cover more fully in how to invest for your grandchildren. A child can only hold one cash and one stocks and shares JISA at a time, and if they already have a Child Trust Fund from the old scheme, it must be transferred into a Junior ISA rather than held alongside one.
- 1
A parent or guardian opens it
Only someone with parental responsibility can set up the account and manage it while the child is young.
- 2
Anyone can contribute
Family and friends can pay in up to the combined £9,000 annual limit: the money is an outright gift to the child.
- 3
It grows tax-free
No income tax or capital gains tax is due on anything the account earns, however large it eventually becomes.
- 4
The child takes over at 16
From their sixteenth birthday the child can manage the account, though they still cannot take the money out.
- 5
They can withdraw at 18
On turning 18 the JISA automatically becomes an adult ISA and the money is theirs to use as they wish.
Cash or stocks and shares?
Cash Junior ISA
- Capital is protected and cannot fall
- Interest is modest and may lag inflation
- Simple and completely predictable
- Best for short horizons or the cautious
Stocks and shares Junior ISA
- Aims for higher long-term growth
- Value can rise and fall along the way
- Suits the long time horizon of a JISA
- Historically outpaces cash over many years
The reason a Junior ISA can be so powerful is time. Money invested for a newborn has around eighteen years to compound, and even modest sums can grow into a meaningful amount over that span: a reminder that starting early matters far more than starting big. Filling the full £9,000 every year is beyond most families and entirely unnecessary; regular contributions of whatever you can spare still add up, especially when several relatives chip in.
For a newborn or young child, that eighteen-year runway is exactly the kind of horizon over which shares have historically rewarded patience, which is why many families choose the stocks and shares route and simply hold a low-cost global fund. That said, investments can fall as well as rise, and this is information rather than personal advice: the right answer depends on your feelings about risk and when the money will be needed. If you would like a professional view, Vetted Wealth’s free service matches you with independently vetted, FCA-regulated advisers through our investment management network, and you can browse more in our investing guides.
In summary
- A Junior ISA is a tax-free account for under-18s, with a £9,000 allowance in 2026.
- It comes in two forms, cash and stocks and shares, and a child can hold one of each.
- Only a parent or guardian can open one, but anyone can pay in up to the annual limit.
- The money is locked away until the child turns 18, when it becomes their adult ISA.
- The long time horizon leads many families to choose the stocks and shares version.
Sources and further reading
- Investing basics MoneyHelper
- Check the Financial Services Register Financial Conduct Authority
- Individual Savings Accounts GOV.UK
Read the full guide
For the complete picture, see our in-depth guide: Investing for Children.
Speak to a vetted investment management specialist
This is free information, not personal advice. When you’re ready, we’ll match you with an independently vetted, FCA-regulated specialist, free, and with no obligation.
