On a child’s account the money sits invested for up to 18 years, so a small annual fee compounds into a real difference. The good news is that several big platforms charge little or nothing for Junior ISAs. The catch is that most of the zero-fee apps you might use for your own ISA don’t offer them, with Freetrade the exception.
Junior ISA fees at a glance
| Platform | Account fee | Dealing | Notes |
|---|---|---|---|
| Hargreaves Lansdown | £0 | £0 online | Widest investment range |
| Fidelity | £0 | Free for funds | No service fee on Junior ISAs |
| Freetrade | £0 | £0 | Launched April 2026; 0.99% FX fee on non-sterling investments on the free plan |
| Vanguard | 0.15%, capped at £375 | £0 | No £48 minimum on Junior ISAs; Vanguard funds only |
| AJ Bell | 0.25% on funds; shares and ETFs capped at £2.50/month | £1.50 funds, £5 shares; regular investing free | |
| Interactive Investor | £0 extra | Plan rates; regular investing free | Needs an adult ii account on the Plus plan (£14.99/month) or higher |
On top of these, you pay each fund’s or ETF’s own ongoing charge (OCF), wherever you hold it.
What each costs as the account grows
Annual platform cost, with investments bought through free monthly regular investing:
| Balance | HL | Fidelity | Freetrade | Vanguard | AJ Bell (funds) |
|---|---|---|---|---|---|
| £5,000 | £0 | £0 | £0 | £7.50 | £12.50 |
| £20,000 | £0 | £0 | £0 | £30 | £50 |
| £50,000 | £0 | £0 | £0 | £75 | £125 |
| £100,000 | £0 | £0 | £0 | £150 | £250 |
Paying the full £9,000 a year from birth would put £162,000 into the account by 18, before any growth. At that size, a percentage fee costs hundreds of pounds a year, so a no-fee provider matters more as the account grows.
Hargreaves Lansdown: free, with the widest range
The HL Junior ISA has no account charge and no online dealing charges. You get access to HL’s full range of funds, shares, ETFs and investment trusts. For most families this is the cheapest option, and HL charges adults 0.35% for the same service. See Hargreaves Lansdown fees explained for the adult charges.
Fidelity: no service fee
Fidelity doesn’t charge its service fee on Junior ISAs, and fund dealing is free. You can start with £100 as a lump sum or £25 a month. If you plan to hold individual shares or ETFs, check Fidelity’s dealing charges first.
Freetrade: free, app-only
Freetrade launched its Junior ISA in April 2026. It has no account fee and no dealing fees, and it’s available on Freetrade’s free Basic plan. You need your own Freetrade account to open one. The main cost to watch is the 0.99% FX fee on the Basic plan when buying shares or ETFs priced in other currencies, such as US shares. It’s the only zero-fee app in this comparison that offers a Junior ISA.
Vanguard: cheap, but not free
Vanguard’s Junior ISA costs 0.15% a year. Unlike the adult account, there’s no £4 a month minimum, so small accounts stay cheap: £3,000 costs £4.50 a year. You can only hold Vanguard’s own funds and ETFs. If you already use Vanguard for yourself, keeping everything in one place may be worth the small fee. See Vanguard ISA fees explained.
AJ Bell: the most expensive of the six
AJ Bell charges the same 0.25% on funds as its adult ISA. Shares and ETFs are capped at £2.50 a month (£30 a year). Monthly regular investing has no dealing charge. With HL and Fidelity charging nothing, AJ Bell is hard to justify for a Junior ISA unless you already hold your own accounts there.
Interactive Investor: free only on the higher plan
ii doesn’t charge extra for a Junior ISA, but you can only open one if you hold an adult ii account on the Plus plan (£14.99 a month) or Premium. It isn’t available on the cheaper Core plan. If you’re already on Plus, every child’s Junior ISA is effectively free. If you’re not, it’s an expensive way in.
Platforms that don’t offer a Junior ISA
Trading 212 and InvestEngine are among the cheapest platforms for adults, so it’s common to use one for your own ISA and a different provider for your child’s.
Junior ISA rules in brief
- Allowance: £9,000 per child for 2026/27, separate from your own £20,000.
- Who can open one: a parent or guardian, for a child under 18 living in the UK. Anyone can pay in.
- Access: no withdrawals until 18, when it becomes an adult ISA in the child’s name. From 16 the child can manage it.
- One of each type: a child can have one Junior Stocks & Shares ISA and one Junior Cash ISA at a time.
- Transfers: you can move a Junior ISA to another provider at any time, and a Child Trust Fund can be transferred into one.
For the rules on adult ISAs, see our guide to holding multiple ISAs.