ISA Allowance Calculator (2026/27)
The ISA allowance is £20,000 per tax year — use it or lose it, with no carry-forward. Enter what you have contributed so far to see how much room you have left before the 5 April deadline.
How it works
You can pay up to £20,000 per tax year across all your ISAs combined — cash, stocks & shares, innovative finance and Lifetime ISA in any mix. The Lifetime ISA has its own £4,000 sub-limit, which counts inside the £20,000 total.
The allowance resets every 6 April and unused allowance is lost permanently — there is no carry-forward. Contributions count when made; withdrawals from most ISAs do not restore allowance unless the provider offers a "flexible ISA".
Interest, dividends and capital gains inside an ISA are entirely tax-free forever and never need reporting to HMRC. Since 2024 you can also pay into multiple ISAs of the same type in one year. Junior ISAs have a separate £9,000 limit that does not affect yours.
FAQ
What is the ISA allowance for 2026/27?
£20,000 across all your adult ISAs combined — unchanged since 2017/18. Within that, a Lifetime ISA can take up to £4,000 (with a 25% government bonus if you are eligible). A separate £9,000 Junior ISA allowance exists per child and does not use up your own.
What happens to unused ISA allowance?
It disappears at midnight on 5 April — there is no carry-forward of any kind. This is why February and March see a rush of "use it or lose it" contributions. Even moving cash into an ISA without choosing investments protects that year's allowance.
If I withdraw money, can I pay it back in?
Only with a "flexible ISA": those let you withdraw and replace money within the same tax year without using fresh allowance. Standard ISAs do not — a withdrawal is simply gone, and re-depositing counts against your remaining £20,000. Check whether your provider offers flexibility before moving money.