Junior ISA allowance: here’s what you need to know

The Junior ISA allowance (JISA) for 2025/26 is £9,000 from 6 April onwards. Learn everything you need to know about JISA allowances, rules and essentials in this guide.

What is the Junior ISA allowance?

At a glance:

•  The Junior ISA allowance for 2025/26 is £9,000
•  Like all ISA allowances, it resets on 6 April each year
•  The Junior ISA allowance is applied per child, meaning each child has £9,000 which can be split across cash Junior ISAs and stocks and shares Junior ISAs
•  Junior ISA allowances can’t be carried over from one tax year to the next
•  Your own adult ISA allowance is not affected by money placed into your child’s Junior ISA

Is the Junior ISA limit per child?

A Junior ISA is a great way to build a pot for your child as they grow up. The current rules mean you can save up to £9,000 each tax year, for each of your children, and this money can be split between a cash Junior ISA and a stocks and shares Junior ISA.

A child can have only one cash Junior ISA and one Junior stocks and shares ISA at any given time, and the money won’t be available until they reach 18, when the account becomes a regular (adult) ISA.

Paying into a Junior ISA

Although you must be the child’s parent or guardian to open an account, anybody can pay into a Junior ISA without affecting their own personal ISA allowance.

Any unused Junior ISA allowance is lost at the end of the tax year and not carried forward.

Junior stocks and shares ISA allowances are reviewed every tax year. The below table displays how the allowances have changed since the Junior ISA was introduced in 2011.

Historically, the Junior ISA allowance has increased but it isn’t certain this will be the case in the future. The limits are set by the government in charge, so it’s possible they’ll change in future tax years.

What happens if I exceed the Junior ISA allowance?

With AJ Bell, there’s no need to worry about exceeding the Junior ISA maximum contribution, as we’ll inform you before payment if it will take the account over the threshold.

However, if you’ve set up and paid into Junior ISAs with other providers in the same tax year, we won’t be able to identify these payments. If you do go over the annual allowance on your child’s Junior ISA, the best thing to do is contact HMRC on 0300 200 3312.

What is the Child Trust Fund allowance?

The Child Trust Fund has a separate annual allowance of £9,000 a year, meaning that no matter how much has been added to it, your child’s Junior stocks and shares ISA allowance is unaffected. As a result, you can add £9,000 to the Child Trust Fund before transferring it into a Junior ISA, then add another £9,000, so that a total of £18,000 could be added this tax year.

Please remember that the Child Trust Fund yearly allowance runs in line with the child’s birthday – starting on their birthday and ending the day before their next birthday. A Junior ISA annual allowance follows the usual tax year, running from 6 April to 5 April the following calendar year.

If you’re thinking of opening a Junior ISA for a child who has an existing Child Trust Fund, it’s important to note they can’t have a Junior ISA and Child Trust Fund at the same time. If they do have a Child Trust Fund, you’ll need to transfer it as part of your Junior ISA application.

Transferring a Junior ISA to AJ Bell

Transferring a Junior ISA or Child Trust Fund to our award-winning platform doesn’t cost a thing. Visit our transfers page to find out more about the process.