The ISA allowance for the 2025/26 tax year is £20,000. You can pay the whole £20,000 into a stocks and shares ISA, or split it across cash, stocks and shares, innovative finance and lifetime ISAs in any combination. The allowance resets every 6 April and cannot be carried forward.
The short answer
- The 2025/26 ISA allowance is £20,000 per person and you can put all of it in a stocks and shares ISA.
- That £20,000 is shared across all ISA types; the lifetime ISA is capped at £4,000 within it.
- The allowance resets on 6 April and cannot be carried forward, unused allowance is lost.
For the 2025/26 tax year the overall ISA allowance is £20,000 per person, and you can direct all of it into a stocks and shares ISA if you wish. That single figure is the ceiling across all the ISAs you hold, cash, stocks and shares, innovative finance and lifetime ISAs share the same £20,000 pot, so paying £12,000 into a cash ISA leaves £8,000 for a stocks and shares ISA in the same year.
The allowance is generous by historical standards and has been frozen at £20,000 since 2017, but it is strictly use-it-or-lose-it. If you do not use the full amount by 5 April, the unused portion vanishes: there is no carry-forward as there is with pensions. That is why many investors top up in the weeks before the tax-year end, or set up a monthly direct debit to spread contributions across the year.
How the £20,000 splits across ISA types
You are free to spread your allowance across the different ISA flavours in almost any combination. The one important sub-limit is the lifetime ISA (LISA): you can pay in a maximum of £4,000 a year, and that £4,000 counts within, not on top of, your overall £20,000. The Government adds a 25% bonus to LISA contributions, but withdrawals before age 60 for anything other than a first home carry a 25% charge, so it suits a narrower set of goals.
ISA types and their 2025/26 limits
| ISA type | Annual limit | Notes |
|---|---|---|
| Stocks and shares ISA | Up to £20,000 | Shares, funds, ETFs, investment trusts and bonds, held tax-free |
| Cash ISA | Up to £20,000 | Interest paid tax-free; capital protected |
| Innovative finance ISA | Up to £20,000 | Peer-to-peer lending; higher risk |
| Lifetime ISA | Up to £4,000 | Counts within the £20,000; 25% Government bonus |
| Junior ISA | Up to £9,000 | Separate allowance for under-18s; does not touch yours |
Note the Junior ISA sits entirely outside your personal allowance. A parent can pay up to £9,000 into a child’s Junior ISA and still use their own full £20,000. If you are saving for children or grandchildren, our guide to investing for children explains how Junior ISAs and other wrappers compare.
Is there a limit on how big my ISA can grow?
No. The £20,000 cap applies only to new contributions each year: there is no limit on the total value an ISA can reach, and no cap on the tax-free growth inside it. Decades of consistent contributions, reinvested dividends and compounding can build an ISA worth several hundred thousand pounds, all shielded from income tax, dividend tax and capital gains tax. This is what makes the wrapper so powerful over a lifetime, and why we cover it alongside how to start investing.
The allowance is per person, per year
A couple can shelter up to £40,000 between two ISAs each tax year. Because unused allowance cannot be reclaimed later, using both partners’ allowances every year is one of the simplest ways to build tax-free wealth.
What if I pay in more than £20,000?
If you accidentally exceed the limit, perhaps by paying into ISAs with two providers, HMRC will usually spot it after the tax year ends and contact you to unwind the excess; you should not try to fix it yourself by withdrawing money without speaking to your provider first. Since April 2024 you have been allowed to pay into more than one ISA of the same type in a year, which makes it easier to spread money around but also easier to lose track, so keep a simple running total.
When in the tax year should you invest?
You can use your allowance in one lump sum, in regular monthly amounts, or a mix of the two: there is no right answer that suits everyone. Investing early in the tax year gives your money the longest possible time to grow tax-free, while spreading contributions monthly smooths out the ups and downs of the market through pound-cost averaging. What matters most is simply using the allowance before it expires: an unused £20,000 is gone for good on 6 April, and you cannot double it up the following year.
If cash flow is tight, even a modest regular contribution keeps the habit going and builds the pot steadily. Many providers let you start from as little as £25 a month, which is why an ISA is often the first port of call for new investors deciding how much they need to start investing.
How much you should put in is a separate question from how much you can. That depends on your goals, your time horizon and whether a pension might be more tax-efficient for some of the money, pension contributions attract tax relief up to a £60,000 annual allowance, which can make them the better home for higher-rate taxpayers. A regulated adviser can model the trade-offs; Vetted Wealth can match you, free of charge, with an independently vetted, FCA-regulated adviser, and you can read more on the investment management pillar. Remember that investments can fall as well as rise, and this is information, not personal advice.
In summary
- The 2025/26 ISA allowance is £20,000 per person and you can put all of it in a stocks and shares ISA.
- That £20,000 is shared across all ISA types; the lifetime ISA is capped at £4,000 within it.
- The allowance resets on 6 April and cannot be carried forward, unused allowance is lost.
- There is no cap on the total value or growth of an ISA, only on annual contributions.
- A couple can shelter up to £40,000 a year; Junior ISAs (£9,000) sit outside your allowance.
Sources and further reading
- Investing basics MoneyHelper
- Check the Financial Services Register Financial Conduct Authority
- Individual Savings Accounts GOV.UK
Read the full guide
For the complete picture, see our in-depth guide: Stocks and Shares ISAs Explained.
Speak to a vetted investment management specialist
This is free information, not personal advice. When you’re ready, we’ll match you with an independently vetted, FCA-regulated specialist, free, and with no obligation.
