Few financial decisions reward patience as richly as investing for a child. Start early with modest monthly contributions, and eighteen years of compounding can turn them into a genuinely life-changing sum — enough to fund a degree, a house deposit, or a first business. Yet the UK tax rules that surround children’s money are specific and occasionally counter-intuitive. Parents and grandparents tend to meet the same handful of questions: which type of account, whose name the money should sit in, how the tax works, and whether a pension for a small child makes any sense at all. This guide looks at the three main options — Junior ISAs, child pensions (SIPPs), and bare trusts — and how families typically choose between them.
Why the timing matters
The single biggest advantage of investing for a child is time. Money saved at birth has eighteen years or more to compound before the child needs it, and most of the growth in a long-term pot comes from reinvested returns rather than the contributions themselves. That long runway also makes children’s investing genuinely tax-efficient: children have their own tax allowances, which most of them never use, so income and gains that would be taxed in an adult’s hands can grow sheltered instead.
There are softer benefits too. An account the child can see, and later understand, teaches financial literacy far better than any conversation about it. And a lump sum at eighteen — for university, a first home, or simply starting out in adult life — gives a young person options that saving from a salary later in life rarely matches.
This is a general introduction rather than personal advice, but it should help you compare the accounts on their own terms and see which best fits your aims.
Junior ISAs: the default choice
A Junior ISA (JISA) is the most popular route, and for good reason. It works like an adult ISA — money grows completely free of UK tax on interest, dividends, and capital gains, and there is no tax to pay when the child withdraws at eighteen — but it sits in the child’s name and is locked until then.
The annual allowance is £9,000 per tax year for 2025/26. A parent or legal guardian opens and manages the account, and anyone else — a grandparent, another relative, a family friend — can contribute towards the same annual limit. You can hold a cash JISA, a stocks and shares JISA, or split the allowance between both.
Which type suits a family depends largely on the time horizon. A cash JISA offers interest that has typically been in the region of 3–5%, with capital guaranteed within FSCS limits, which suits risk-averse families or shorter-term goals; high street banks and NS&I offer these. A stocks and shares JISA has historically delivered returns of roughly 7–8% over long periods, but the value can fall as well as rise, so providers such as Vanguard, Hargreaves Lansdown, and AJ Bell tend to be used where the money will not be needed for ten years or more.
There is one rule parents in particular should know. If a parent contributes to a JISA and the child’s total income from it — interest, dividends, and so on — exceeds £100, all of that income is taxed as the parent’s, not the child’s. The threshold applies per parent, per child, and the rule mainly bites on large cash gifts earning interest; for most ordinary JISA contributions it is not a problem, but it is worth bearing in mind before depositing very large sums. It does not apply to gifts from grandparents or other non-parents, though anti-avoidance rules can still apply in some cases.
Child pensions: tax relief and very long horizons
A Junior Self-Invested Personal Pension (SIPP) is less well known than a JISA but offers one thing no other children’s account does: tax relief on contributions. A parent or guardian can contribute up to £2,880 per tax year, and the government adds 20% basic-rate relief automatically, boosting the amount to £3,600. In effect, the state adds £720 for every £2,880 you put in.
The money grows free of tax inside the pension wrapper, and the child — once grown — can take 25% of the pension tax-free, with the rest drawn as taxable income. Pension contributions also sit outside your estate for inheritance tax purposes. As a rough illustration, £3,600 invested each year from birth at an average 7% growth would look something like this:
| Age | Approximate value |
|---|---|
| 10 | £52,000 |
| 18 | £134,000 |
| 30 | £350,000 |
| 57 | £2,100,000+ |
That is built on just £2,880 a year of your own money; tax relief and over half a century of compounding do the heavy lifting.
The trade-off is access. A child cannot touch the pension until age 57 under current rules (rising from 55), so a SIPP makes little sense if the money is meant for university or a first home — those are JISA goals. It is best thought of as a long-term retirement boost, where even small amounts grow enormously over fifty or more years.
Bare trusts and general investment accounts
A bare trust is not a tax wrapper. It is a simple legal arrangement in which investments are held in a general investment account in the child’s name, with a little trust scaffolding around it. There is no contribution limit, and money can be withdrawn before the child turns eighteen with proper trust administration — which is its defining appeal.
The tax treatment uses the child’s own allowances: their £12,570 Personal Allowance shelters income, and they have their own capital gains tax annual exempt amount. Because most children use very little of these allowances, a bare trust can be surprisingly tax-efficient for larger gifts. Two caveats: if the money came from a parent and generates more than £100 of income a year, the parental rule applies here too; and contributions may be treated as gifts for inheritance tax purposes, falling back within the parent’s estate if they die within seven years.
A bare trust is worth considering when you want maximum flexibility over how the child accesses money, when you want to invest more than the £9,000 JISA limit, or when you are comfortable managing a trust — or paying an adviser to. The costs are a higher administrative burden, the inheritance tax considerations, and the fact that the child receives the money outright at eighteen, with no control over how they spend it. Regulated ISA and pension products also come with more consumer protection than a bare trust.
Choosing between them
A JISA suits flexibility: simple accounts, tax-free growth, £9,000 a year, and clean access for university or a first home at eighteen. A child SIPP suits the very long term, where the 20% relief and decades of compounding outweigh locking the money away until 57. A bare trust or general investment account suits larger gifts and maximum flexibility, at the cost of administration and inheritance tax considerations.
Many families simply combine: a JISA for the money the child may need at eighteen, and a SIPP for retirement. Together they allow up to £9,000 and £2,880 — £11,880 a year — into tax-efficient wrappers.
A worked example
Imagine investing £200 per month from birth into a stocks and shares JISA, at an illustrative 7% average annual growth:
| Age | Total contributed | Estimated value |
|---|---|---|
| 5 | £12,000 | £14,400 |
| 10 | £24,000 | £34,500 |
| 15 | £36,000 | £63,200 |
| 18 | £43,200 | £91,500 |
You contribute £43,200 and the account is worth over £91,000 — nearly £48,000 of tax-free growth the child can use for university, a first home, or anything else. Add a child SIPP funded with £240 a month (which tax relief turns into £300), and the combined pot at eighteen would be meaningfully larger again, with the pension portion having more than 57 further years to grow.
Tax rules to keep in mind
Beyond the £100 parental rule, remember that children hold the same personal allowances as anyone else. As of the figures quoted in this guide, that means a Personal Allowance of £12,570 with no income tax on the first £12,570, a Personal Savings Allowance of £1,000 for basic-rate or £500 for higher-rate taxpayers, a Dividend Allowance of £500, and a capital gains tax annual exempt amount of £3,000. For most children these allowances are more than enough to shelter investment income — which is why a bare trust can be so efficient.
A final word
None of this should be read as a recommendation to act today; rates, allowances, and rules change, and every family’s needs are different. What holds up is the general principle: contributions started early, made consistently, and allowed to compound tax-efficiently for nearly two decades are the most reliable way to give a child a financial foundation. Even £50 or £100 a month, invested from birth, accumulates to a meaningful sum — and the earlier the account is opened, the more the calendar does the work.