What's an ISA allowance?
The value of your investments and the income from them may go down as well as up, and you could get back less than you invested.
Tax treatment depends on the individual circumstances of each client and may be subject to change in the future.
Because of their generous tax benefits, the Government limits how much money you can put into ISAs. For the 2025/26 tax year the ISA allowance is a generous £20,000. You can split your allowance across a Stocks & Shares ISA and Cash ISA or invest it all in either one. The Junior ISA allowance for investing for children is £9,000.
Your ISA allowance resets every year
At the beginning of each new tax year your annual ISA allowance resets. You cannot carry your allowance over between years, so if you don’t use it you lose it. In April 2016 the Government made changes that allow you to take money out of your ISA and replace it in the same tax year without using up your allowance.
Junior ISA allowance
This tax year you can pay up to £9,000 into a Junior ISA for a child. From age 16 a child can also have an adult cash ISA alongside their Junior ISA. They can still only keep £9,000 per tax year in the Junior ISA, but they could also save up to £20,000 extra in an adult cash ISA between age 16 and 18. From 6 April 2027, they can save up to £8,000 extra in an adult cash ISA between age 16 and 18.
Historical ISA allowances
The ISA and Junior ISA allowances are reviewed each tax year (which runs from 6 April to 5 April). This table shows how both allowances have changed over the last few tax years.
| Tax year | ISA allowance | Junior ISA allowance |
| 2025/2026 (current tax year) | £20,000 | £9,000 |
| 2024/2025 | £20,000 | £9,000 |
| 2023/2024 | £20,000 | £9,000 |
| 2022/2023 | £20,000 | £9,000 |
| 2021/2022 | £20,000 | £9,000 |
| 2020/2021 | £20,000 | £9,000 |
| 2019/2020 | £20,000 | £4,368 |
| 2018/2019 | £20,000 | £4,260 |
| 2017/2018 | £20,000 | £4,128 |
| 2016/2017 | £15,240 | £4,080 |
| 2015/2016 | £15,240 | £4,080 |
| 2014/2015 | £15,000 | £4,000 |
Speak to an expert about ISAs
Find out more about your ISA allowance and our award-winning Stocks & Shares ISA by speaking to our experts:
How Bestinvest can help
Looking for an efficient way to invest? Become a Bestinvestor with a Stocks & Shares ISA (Individual Savings Account) and save tax free.
Wondering what your ISA could be worth? Use our ISA calculator and stay on track the easy way.
Important Information
Tax and ISA rules may be subject to change from time to time
With investment, your capital is at risk.
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