🏦 UK ISA Allowance Checker

An ISA (Individual Savings Account) is a tax-efficient wrapper available to UK residents that shelters your savings and investments from Income Tax and Capital Gains Tax. Every tax year (running from 6 April to 5 April the following year), each adult aged 18 and over is entitled to an annual ISA allowance of GBP 20,000. This is the maximum total amount you can pay into ISA accounts across all ISA types combined during that tax year.

The GBP 20,000 allowance can be split between several types of ISA in any proportion you choose. The four main adult ISA types are: Cash ISA (savings held in cash, with interest paid tax-free), Stocks and Shares ISA (investment in funds, shares, bonds, and ETFs, with growth and dividends free from tax), Lifetime ISA (LISA) (designed for first home purchase or retirement, with a 25% government bonus on contributions, but capped at GBP 4,000 per year which counts within your GBP 20,000 overall allowance), and Innovative Finance ISA (IFISA) (for peer-to-peer lending and crowdfunding investments).

In addition, a Junior ISA (JISA) is available for children under 18, with a separate allowance of GBP 9,000 per child per tax year. JISA contributions do not count against the adult GBP 20,000 allowance, making it a powerful vehicle for intergenerational wealth planning. 16 and 17-year-olds can have both a Cash ISA and a Junior ISA simultaneously, giving them access to the full GBP 20,000 adult Cash ISA allowance plus the full GBP 9,000 Junior ISA allowance.

Under HMRC rules, you cannot exceed the GBP 20,000 limit across all your ISAs in a single tax year. You also cannot open a new ISA of the same type with a different provider and pay into both in the same tax year, but you can transfer old ISA balances between providers without affecting your current year allowance. The transfer must be done between providers directly; withdrawing money and re-depositing it would use up your current year allowance.

This checker sums your current-year contributions across all ISA types, calculates how much of your GBP 20,000 allowance remains, flags if you have exceeded the LISA sub-limit of GBP 4,000, and shows your JISA usage separately.

The checker takes five inputs for the current tax year (6 April 2026 to 5 April 2027): amounts contributed to each adult ISA type (Cash ISA, Stocks and Shares ISA, Lifetime ISA, and Innovative Finance ISA), and your Junior ISA contributions. It sums the adult contributions and compares the total against the GBP 20,000 annual ISA allowance.

The LISA contribution is also checked against its own sub-cap of GBP 4,000. If you have paid more than GBP 4,000 into a LISA, the excess will be flagged. Note that any amount you put into a LISA counts against your overall GBP 20,000 allowance too, so it is not in addition to it.

The checker processes JISA contributions separately, since the JISA GBP 9,000 limit does not interact with the adult allowance. The summary table below shows how all the limits work together:

1. Enter the amount you have paid into your Cash ISA this tax year.
2. Enter your Stocks and Shares ISA contributions.
3. Enter your Lifetime ISA (LISA) contributions.
4. Enter your Innovative Finance ISA (IFISA) contributions.
5. Enter any Junior ISA (JISA) contributions for a child.
6. Click Calculate to see your total used, remaining allowance, and LISA compliance.

What is the UK ISA allowance for the 2026/27 tax year?

The annual ISA allowance is GBP 20,000 per adult. You can split this across Cash ISA, Stocks and Shares ISA, Lifetime ISA (max GBP 4,000), and Innovative Finance ISA in any combination.

Does the Lifetime ISA GBP 4,000 limit count toward my GBP 20,000?

Yes. The GBP 4,000 LISA sub-limit is part of the overall GBP 20,000 annual ISA allowance, not in addition to it. If you put GBP 4,000 into a LISA, you have GBP 16,000 left for other ISA types.

What is the Junior ISA allowance?

The Junior ISA (JISA) allowance is GBP 9,000 per child per tax year. This is completely separate from the adult GBP 20,000 allowance and does not count against it.

Can I open more than one ISA of the same type in the same tax year?

You can hold multiple ISAs of different types in the same tax year, but you cannot pay into two ISAs of the same type (for example, two Cash ISAs with different providers) in the same tax year. However, you can transfer an existing ISA to a new provider without affecting your current year allowance.

What happens if I accidentally pay in more than GBP 20,000?

HMRC charges a 25% charge on the excess amount. You should contact your ISA provider immediately to arrange withdrawal of the excess contribution and contact HMRC to settle any charge.

This tool is for informational purposes only and does not constitute financial advice. Consult a qualified financial professional for advice specific to your situation.

The ISA allowance is strictly use-it-or-lose-it: any unused portion cannot be carried forward to the next tax year, so make sure you deposit before 5 April. If you have already maxed out your allowance and want to move ISAs between providers, use the official transfer process, not a withdrawal and redeposit. Withdrawing and re-depositing within the same tax year does not give you back your allowance unless the ISA has a flexible feature (Cash ISAs are often flexible, but Stocks and Shares ISAs typically are not). For a Lifetime ISA, remember the GBP 4,000 sub-limit means you can put at most GBP 4,000 into the LISA and the remaining GBP 16,000 into other ISA types. JISAs are a powerful tool: even if you are not a UK taxpayer, the returns are completely tax-free. If your child turns 18 and the JISA becomes an adult ISA, the allowance is not carried over: the GBP 20,000 limit applies from that point. Finally, do not forget that transferring a LISA out means the receiving provider must accept LISAs, and some do not.