The ISA allowance for 2025/26 is £20,000. This is the maximum across all ISAs combined. The tax year runs from 6 April 2025 to 5 April 2026. Unused allowance cannot be carried over. From April 2027, under-65s may be limited to £12,000 in Cash ISAs.
The ISA allowance is one of the most generous tax breaks the UK government offers, yet millions of people do not use it each year. Here is everything you need to know.
What Is the ISA Allowance?
The ISA allowance is the maximum you can deposit into ISAs in a single tax year. For 2025/26, it is £20,000. This is a combined limit across all ISA types: Cash ISA, Stocks and Shares ISA, Lifetime ISA, and Innovative Finance ISA.
The tax year runs from 6 April to 5 April. The deadline to use your 2025/26 allowance is midnight on 5 April 2026.
How Can I Split My ISA Allowance?
You have complete flexibility. Examples: all £20,000 into a Stocks and Shares ISA; £10,000 cash and £10,000 investments; or £8,000 cash, £8,000 investments, and £4,000 into a LISA. The only restriction is the LISA sub-limit of £4,000.
If you are deciding how to split between cash and investments, my guide on cash vs stocks and can help.
ISA Allowance by Type
| ISA Type | Max | Tax Benefits | Best For |
|---|---|---|---|
| Cash ISA | £20,000 | Tax-free interest | Short-term savings |
| S&S ISA | £20,000 | Tax-free growth + dividends | Long-term investing (5yr+) |
| Lifetime ISA | £4,000 | 25% govt bonus + tax-free | First home / retirement |
| Junior ISA | £9,000* | Tax-free growth | Children under 18 |
*Junior ISA allowance is separate from the adult £20,000 limit.
I cover the Junior ISA in my Junior ISA guide and LISA rules in my LISA rules guide.
Can I Have Multiple ISAs?
Yes. Since April 2024, you can open and pay into multiple ISAs of the same type in a single tax year, as long as total contributions stay within £20,000. My guide on multiple ISAs explains how this works.
What Happens If I Exceed the Allowance?
HMRC will remove the tax benefits on the excess amount. Your provider may void the excess contribution. It is your responsibility to track your total across all providers.
Can I Carry Over Unused Allowance?
No. The allowance resets every tax year and unused portions are lost forever. Even small monthly contributions help you make the most of it. Trading 212 lets you start a free ISA from £1. See my Trading 212 Stocks and Shares IS.
Upcoming ISA Changes for April 2027
The government has proposed limiting Cash ISA contributions to £12,000 per year for under-65s from the 2027/28 tax year. The full £20,000 would remain for Stocks and Shares ISAs and for over-65s.
If you have been thinking about opening a Stocks and Shares ISA, now is a good time. My guide on stocks and covers how they work.
ISA Allowance History
| Tax Year | Allowance |
|---|---|
| 2025/26 | £20,000 |
| 2017/18 - 2024/25 | £20,000 |
| 2016/17 | £15,240 |
| 2014/15 | £15,000 |
| 2013/14 | £11,520 |
The allowance has been frozen at £20,000 since 2017/18.
How to Make the Most of Your ISA Allowance
Start early in the tax year. The sooner you invest, the longer your money has to grow.
Set up regular contributions. Monthly investing (pound-cost averaging) is simple and effective.
Use the right ISA type. Cash for short-term, stocks and shares for long-term.
Do not let the allowance go to waste. £200/month for 20 years at 7% growth = over £100,000, all tax-free.
Compare the best platforms in my best stocks and sha guide.
Frequently Asked Questions
£20,000 across all ISA types combined.
No. The £20,000 is a combined total.
No. Transferring between providers does not count as a new contribution.
Only with a 'flexible' ISA. Otherwise, withdrawals do not restore used allowance.
Up to £4,000 per year, counting towards your overall £20,000. My __LISA rules__ guide explains.
