Investing6 providers Updated May 2026

Best UK Junior ISA (JISA) 2026

Quick answer - our pick

Interactive Investor

Best for: Parents who already hold an Interactive Investor adult account or are willing to switch

For families where a parent or guardian already holds (or is willing to open) an Interactive Investor adult account, the JISA is genuinely free - zero platform fee, full broad fund range, same login as the parent account for easy oversight. For everyone else, Fidelity is the cleanest no-fee alternative with a comparable fund universe. Vanguard and AJ Bell are both reasonable next-tier picks if you want a specific fund range. Hargreaves Lansdown's 0.45% headline fee compounds over an 18-year horizon into hundreds of pounds of unnecessary cost. Cash JISAs (including NS&I) make sense only if the contributors genuinely want the safety; for an 18-year time horizon, equities are statistically the right answer.

Visit Interactive Investor See full comparison
A Junior ISA (JISA) is a tax-free savings or investment account opened in a child's name. Anyone can contribute and the £9,000 annual allowance (2026/27) is per child, not per contributor. The pot is locked until the child turns 18, at which point it converts to an adult ISA in their name and they have full control of the money. Most UK Junior ISAs are either Cash JISAs (savings-account format) or Stocks and Shares JISAs (invested in funds or ETFs). For a child with 18 years to compound, the Stocks and Shares variant typically dwarfs cash on long-run returns. We rank the main UK platforms on cost, fund choice and contribution mechanics. For the parent-side accounts, see our [Stocks and Shares ISA comparison](/compare/stocks-shares-isa) and [Lifetime ISA comparisons](/compare/stocks-shares-lisa).

Annual platform fee on a £20,000 JISA pot

Indicative platform fee only. Excludes fund OCFs (typically 0.10% to 0.25% for trackers) and dealing fees. Most parents will hold £10k-£50k by age 18 if contributing the full £9k annual allowance from early childhood. Provider names link to each platform's published fee schedule.

Full comparison

Provider JISA typesPlatform fee Best for
Interactive InvestorS&S JISAFree with parent accountParents who already hold an Interactive Investor adult account or are willing to switch
FidelityS&S JISA0% (no service fee on JISA)Parents who want zero ongoing JISA cost with a broad mutual-fund universe
VanguardS&S JISA0.15% (capped at £375/year across all Vanguard accounts)Vanguard loyalists who want a single platform for their own ISA, SIPP and the child's JISA
AJ BellS&S JISA0.25% (capped at £42/year on shares)Parents who want the same fund universe as their adult ISA without changing platforms
Hargreaves LansdownS&S JISA0.45% (capped at £45/year on shares)Parents who value premium service and tooling enough to pay double on fees
NS&I Junior ISACash JISANo feesGrandparents and family members wanting absolute safety, or contributors who insist on sovereign-backed cash

Provider details

Interactive Investor

Parents who already hold an Interactive Investor adult account or are willing to switch

JISA typesS&S JISA
Platform feeFree with parent account
Fund universeBroad (40,000+ instruments)
Min investment£25

Pros

  • Junior ISA is completely FREE if a parent or guardian has an Interactive Investor account
  • Cheapest option for high-balance JISAs because there is literally no fee
  • Access to the same broad fund range as the parent account

Cons

  • Requires at least one parent to hold an Interactive Investor adult account (£4.99-£21.99/month)
  • No Cash JISA option
  • £25 minimum per trade is high for very small monthly contributions
Interactive Investor JISA page Visit Interactive Investor →

Fidelity

Parents who want zero ongoing JISA cost with a broad mutual-fund universe

JISA typesS&S JISA
Platform fee0% (no service fee on JISA)
Fund universeBroad (3,000+ funds)
Min investment£25

Pros

  • Zero platform service fee on the Junior ISA (parent accounts still charge 0.35%)
  • Free regular investing into funds
  • Strong educational content and research

Cons

  • £7.50 per share trade if you hold individual shares
  • No Cash JISA
  • JISA fund range is broad but not unlimited - some niche ETFs unavailable
Fidelity Junior ISA page Visit Fidelity →

Vanguard

Vanguard loyalists who want a single platform for their own ISA, SIPP and the child's JISA

JISA typesS&S JISA
Platform fee0.15% (capped at £375/year across all Vanguard accounts)
Fund universeVanguard funds only
Min investment£100

Pros

  • Hard fee cap at £375/year across all Vanguard wrappers combined
  • Direct access to LifeStrategy and Target Retirement funds
  • Same parent-friendly interface as the main Vanguard platform

Cons

  • Vanguard funds only - no third-party trackers
  • £100 minimum opening contribution is higher than rivals
  • No Cash JISA
Vanguard fees page Visit Vanguard →

AJ Bell

Parents who want the same fund universe as their adult ISA without changing platforms

JISA typesS&S JISA
Platform fee0.25% (capped at £42/year on shares)
Fund universeBroad (2,000+ funds)
Min investment£25

Pros

  • Same broad fund range as the AJ Bell adult ISA
  • £42/year cap on share/ETF custody fees
  • Decent app for parent oversight of contributions

Cons

  • 0.25% platform fee on funds compounds over an 18-year horizon
  • £1.50 per fund trade adds up if contributing monthly
  • No Cash JISA
AJ Bell charges page Visit AJ Bell →

Hargreaves Lansdown

Parents who value premium service and tooling enough to pay double on fees

JISA typesS&S JISA
Platform fee0.45% (capped at £45/year on shares)
Fund universeVery broad (3,000+ funds)
Min investment£100

Pros

  • Most polished UX of any UK JISA platform
  • Strong customer service for first-time JISA parents
  • Tiered fund fee drops to 0.25% above £250k (rarely relevant in a JISA)

Cons

  • 0.45% is roughly 2x cheaper alternatives, and 18 years of compounding makes this matter
  • £11.95 per share trade if holding individual shares
  • £100 minimum opening
Hargreaves Lansdown charges page Visit Hargreaves Lansdown →

NS&I Junior ISA

Grandparents and family members wanting absolute safety, or contributors who insist on sovereign-backed cash

JISA typesCash JISA
Platform feeNo fees
Fund universeCash only (interest-bearing)
Min investment£1

Pros

  • Sovereign-backed - not subject to the £85k FSCS limit
  • No platform fees at all
  • £1 minimum opening - the lowest barrier to entry of any JISA

Cons

  • ~3.7% interest rate (variable) lags equity-tracker returns by ~3-4 percentage points over 18 years
  • No investment growth potential - cash only
  • For an 18-year horizon, the lost compound growth is substantial
NS&I Junior ISA page Visit NS&I Junior ISA →

Honourable mentions

Fidelity

Runner-up

Best for: Parents who want zero ongoing JISA cost with a broad mutual-fund universe

No-fee JISA with a broad fund range and no parent-account requirement. The most accessible option for families who don't want to hold a paid adult account at the same provider.

Visit Fidelity →

Vanguard

Runner-up

Best for: Vanguard loyalists who want a single platform for their own ISA, SIPP and the child's JISA

If you're already running Vanguard for your own ISA and SIPP, adding the JISA under the same £375 hard cap makes the marginal cost trivial. The fund range is narrow but the LifeStrategy options are exactly what you want for a child's long-horizon portfolio.

Visit Vanguard →

AJ Bell

Runner-up

Best for: Parents who want the same fund universe as their adult ISA without changing platforms

If you want a single provider for every UK wrapper (Cash ISA, S&S ISA, LISA, SIPP, JISA, JSIPP, GIA) under one login, AJ Bell is the most complete option. The 0.25% fee is the cost of that consolidation.

Visit AJ Bell →

How we picked

Fees verified from each provider's public JISA page, last reviewed May 2026. The Cash JISA and Stocks and Shares JISA are different products with different mechanics; this comparison covers Stocks and Shares JISAs primarily because the 18-year horizon overwhelmingly favours equities. Where a provider offers both cash and invested variants, we note the cash option separately.

What is a UK Junior ISA?

A Junior ISA (JISA) is a tax-free savings or investment account held in a child's name and managed by a parent or guardian until the child turns 18. At 18 it converts automatically into an adult ISA and the now-adult takes full control of the money. The £9,000 annual allowance (2026/27) is per child and per tax year. Anyone can contribute - parents, grandparents, godparents, generous aunts - but the total across all contributors can't exceed £9,000 per child. The wrapper exists in two flavours: Cash JISA (savings account format with interest) and Stocks and Shares JISA (invested in funds, ETFs or shares). A child can hold one of each type per tax year but only contribute to one of each in any single year. Key constraints worth knowing: - The money is locked until the child's 18th birthday. There is no early access for any reason, including university fees or a first car. The child decides what happens at 18. - A child can't have both a JISA and a Child Trust Fund (CTF) simultaneously. CTFs were the predecessor scheme that ran 2002-2011; if your child has a CTF you can transfer it to a JISA but you can't open both. - The £9,000 allowance is separate from the adult £20,000 ISA allowance and doesn't affect it. - The pot doesn't belong to the parent in any meaningful sense - it's the child's money from the moment a contribution is made. Contributors give it up legally and irreversibly.

Stocks and Shares JISA vs Cash JISA

For an 18-year time horizon, the maths overwhelmingly favours Stocks and Shares. A Cash JISA pays interest at typically 3% to 4.5% (May 2026 rates). Over 18 years, £100/month compounded at 4% grows to roughly £31,400 - about £21,400 of contributions plus £10,000 of interest. Decent but not transformational. A Stocks and Shares JISA invested in a global equity tracker has historically returned around 7% nominal (5% real after inflation). The same £100/month over 18 years at 7% grows to roughly £43,300 - about £21,400 of contributions plus £21,900 of investment growth. That's £12,000 more than the Cash JISA on the same monthly contribution. The behavioural objection - 'but equities are risky' - is real for short horizons but vanishes at 18 years. The longest period in modern UK and US history where a globally-diversified equity portfolio underperformed cash over 18 years is... none of them. The same is not true at 5 years, 10 years, or even 15 years. But at 18, the equity premium is the dominant signal in the data. The one case for Cash JISA: grandparents or family members who want certainty more than they want optimal returns, and who'd be unhappy seeing the value temporarily drop during a market crash. Their feelings count too. Cash JISA is the right answer for them - just understand the trade-off. Our Cash ISA comparison covers Cash JISA-equivalent rates from the main UK savings providers, but the JISA-specific market is narrower.

How to use the £9,000 allowance well

Most families never come close to the £9,000 annual cap. The realistic question is how to deploy whatever you can afford in a way that maximises long-run growth and minimises friction. **Start at birth.** A JISA opened at birth and contributed to until age 18 has 18 full years of compounding. The same contributions starting at age 5 lose nearly a third of the end value. Even £25/month from birth materially outperforms £100/month from age 10. **Use regular monthly contributions over lump sums.** Most platforms allow standing-order regular investing from £25/month. It's behaviourally easier to commit to a small monthly amount than to find an annual £3,000. The pound-cost-averaging benefit is real but secondary. **Don't fund a JISA before your own pension or ISA is sorted.** Pension contributions get tax relief; JISA contributions don't. ISA contributions are accessible to you; JISA contributions belong to the child at 18 with no come-back. The right priority order is your own retirement first, your own emergency fund second, your child's JISA third. **Tell grandparents about the JISA early.** Grandparents are the single biggest under-contributor to UK JISAs because most don't know they can pay into them. A grandparent who contributes £100 each Christmas birthday for 18 years adds £1,800 of principal plus the compound growth - the difference between a £30k pot and a £37k pot at 18. **Hold a global tracker.** Vanguard LifeStrategy 80 or 100, HSBC FTSE All-World, or an equivalent. Avoid concentrated single-country or single-sector funds; the pot is small enough that diversification matters disproportionately.

What happens when the child turns 18?

On the morning of the child's 18th birthday, the JISA legally converts to an adult Stocks and Shares ISA (or Cash ISA, matching the underlying type). The child now has full control and can withdraw the money, contribute more, transfer to a different provider, or leave it alone. Most UK platforms send a notification to the registered email address roughly 30 days before the 18th birthday explaining what's about to happen. The child should be primed for this before it lands, because the emotional difference between 'I have £30k of unrestricted money' at age 17 versus 18 is significant. The honest framing for parents who are nervous about handover: the legal control transferring at 18 is irreversible and non-negotiable. You can't lock the money up further. You can't gate access to university outcomes or driving licences. The child can spend the entire balance on whatever they want from their 18th birthday onwards. If that prospect troubles you, you should have a conversation with the child during their late teens about what the money is and isn't for - rather than relying on the structure to enforce your preferences. Worker-protective angle: this child-controlled-at-18 design is one of the few financial structures in UK law that genuinely puts a young adult in charge of meaningful capital. Compare with student loans, which lock graduates into 30 years of repayments before they have the financial literacy to evaluate the deal. The JISA hands an 18-year-old enough to make a real choice - housing deposit, university buffer, business seed, or savings continuity - and trusts them with it. Treat that as a feature, not a bug.

How to choose a JISA platform

The shortlist for most UK families: - **Interactive Investor** if a parent already holds (or is willing to open) an II adult account. The JISA is then completely free, which is unbeatable on cost. - **Fidelity** for parents without an II adult account who want zero ongoing fees and a broad fund range. - **Vanguard** for parents already running Vanguard for their own ISA and SIPP, where the JISA falls under the same £375 hard fee cap across all accounts. - **AJ Bell** for families wanting one provider for every UK wrapper including LISA, JSIPP and parent SIPP. Avoid Hargreaves Lansdown unless you genuinely value the premium service - the 0.45% headline fee compounds over 18 years into hundreds of pounds of unnecessary cost. Avoid pure Cash JISAs unless the contributors actively want the safety; for an 18-year horizon, equities win. The one switch that's genuinely worth making: if you're holding a Child Trust Fund (CTF) from before November 2011, transfer it to a JISA. CTFs typically have higher fees and narrower fund choice than modern JISAs.

Frequently asked questions

Who can open a UK Junior ISA?
A parent or legal guardian can open a JISA for a child under 18 who is UK resident. From age 16 the child can manage their own JISA but cannot withdraw until 18. Once opened, anyone can contribute to it (parents, grandparents, godparents) provided the total across all contributors stays within the £9,000 annual allowance.
Can I have both a Junior ISA and a Child Trust Fund?
No. A child can hold one or the other but not both. If your child has a Child Trust Fund (CTFs ran 2002 to 2011), you can transfer it to a Junior ISA to access a wider fund range and typically lower fees. The transfer doesn't count against the annual £9,000 JISA allowance.
How much can I pay into a Junior ISA each year?
The 2026/27 annual allowance is £9,000 per child, shared across all contributors (parents, grandparents, anyone). You can pay this into a Cash JISA, a Stocks and Shares JISA, or split it between the two - but a child can only hold one Cash JISA and one Stocks and Shares JISA at any time, and can only fund one of each per tax year.
When can the child access the money?
The pot is locked until the child's 18th birthday with no exceptions for any purpose. On the 18th birthday it automatically converts to an adult ISA in the child's name and they get full control - they can withdraw, leave it invested, or transfer to another provider. There is no parental override at 18.
Should I open a JISA or pay into my own ISA instead?
Pay your own ISA, your own pension (with employer match), and build an emergency fund FIRST. JISA money belongs to the child at 18 with no come-back; you cannot use it to bail yourself out in an emergency. Only fund the JISA once your own financial floor is solid. The exception is grandparents and other relatives, for whom contributing to a child's JISA is often the easiest way to gift money with long-run impact.
Can grandparents pay into a Junior ISA?
Yes, anyone can contribute to a JISA. Grandparents are particularly well-suited because they're often less constrained on their own ISA/pension allowances and can spread inheritance tax mitigation across multiple grandchildren. Tell them early - grandparents are the most common under-contributor to UK JISAs because most parents don't mention the option.
What if my child doesn't want the money at 18?
It's their money. They can leave it inside the (now adult) ISA wrapper and keep it invested tax-free indefinitely. Many JISA recipients at 18 do exactly this - the tax-free growth continues, they just now have the legal option to access it. The wrapper doesn't dissolve at 18; only the parental control does.

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