Do you know 67% UK savers are unsure what the ISA allowance is? Though ISA is a very popular tax-saving way.
Most UK savers know ISAs exist. But knowing about something and actually using it correctly are two very different things. Millions of people either underuse their annual ISA allowance or don’t fully understand which type of ISA suits their situation.
That matters more right now than it ever has. HMRC is proposing to cut the Cash ISA limit from April 2027. Which means 2026/27 could be the last tax year with a full £20,000 allowance across all ISA types.
If you’ve been putting this off, now is the time to understand exactly what the ISA allowance is, how it works, and how to use every pound of it before the deadline hits.
What is ISA?
An Individual Savings Account (ISA) is a tax-free savings or investment account tailored by HMRC. It is a popular tax-efficient way to save and invest your money available to UK taxpayers. Any returns, interest, or gains on the investments are 100% free from Income Tax and Capital Gain Tax.
You can hold your income in cash and a range of investments within this scheme. There are no restrictions or limitations on when or how much to withdraw. Means you can withdraw your savings at any time without paying any tax. You don’t even need to declare any ISA interest, income, or capital gains while filing a Self Assessment tax return.
What is Isa Allowance?
ISA allowance is the highest amount you can save in your Individual Savings Account in a tax year. You won’t have to pay any tax on the money you earn from your savings.
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In the 2026/2027 tax year, you can save up to £20,000 using your ISA Allowance in an ISA or divide it among multiple ISAs. But remember, you can’t pay more than this limit.
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Generally, the tax year runs from 6th April to 5th April the following year. You can’t move the ISA allowance from one tax year to the next. If you don’t use your total allowance before 5th April, you can’t use the rest of this tax year’s allowance. Any savings in the ISA after 5th April will count as part of the ISA allowance for the following tax year.
Who Can Open an ISA?
According to HMRC, you can open an ISA if you are-
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- A UK resident aged 18 years or over Â
- For a Lifetime ISA, your age must be under 40
- A crown service holder (e,g., diplomatic or overseas civil service)
- A member of overseas armed forces and his/her spouse (civil partner)
How Many Types of ISAs are There?
There are four types of ISAs available in the UK. These are:Â
Cash ISA
Cash ISAs are simply savings accounts where you never pay any tax on earnings. It is a short-term, effective way to save. In the UK, each tax year, a taxpayer aged 18 or over can use a cash ISA. For 2026/2027, the cash ISA is £20,000.
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Some cash ISAs have fixed rates, where you will get a guaranteed interest rate. But you have to keep your cash for a set period. Again, some ISAs offer variable rates and instant access. You can withdraw your money instantly if needed.Â
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HMRC introduced a change from April 2027 for the cash ISA to encourage more people to invest in stocks and shares ISAs. The cash ISA limit will reduce to £12,000 aged 64 or under. But there will be no change for those aged 65 or older, and allowances remain £20,000.Â
Stocks & Shares ISA
Keeping ISA allowance split into different shares, bonds, and funds is known as Investment ISAs. Income or gains from investment are tax-free and different from the cash ISAs. The value of your investments may go up or down. Also, you can’t carry over any unused allowance.Â
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You can not transfer money from stocks and shares ISAs into cash ISAs. Putting money in stocks and shares ISAs works better for medium to long-term periods instead of short-term. Stocks and shares ISAs, including:
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- shares in companies
- unit trusts and investment funds
- corporate bonds
- government bonds
- long-term asset funds
Innovative Finance ISA
An innovative finance ISA is a tax-saving way that allows you to use the ISA allowance in investing in peer-to-peer (P2P) lending. Means you give loans to other people or businesses without using a bank.Â
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Again, you buy a business’s debts by investing your ISA allowance, which is known as crowdfunding debentures. You get your investment return with interest, and this earned interest is tax-free. Cryptoasset exchange-traded notes are also included in the innovative finance ISA.Â
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You can not invest your innovative finance ISA in long-term asset funds unless they were held there before 6 April 2026. Keep them in the stocks and shares ISA. You cannot transfer any previous investments into an innovative finance ISA.
Lifetime ISA
A Lifetime Individual Savings Account LISA) is a tax-saving wrapper designed by HMRC for people aged 18 to 39. It encourages UK taxpayers to save for buying a first home or for later life (retirement).Â
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It helps you save up to £4,000 each tax year, and you will get a 25% bonus in your savings, which can be up to £1,000 per year. You can save up to 50 years old. You can not save or do not receive the 25% bonus when you are aged 50. Your account will keep running, and your earnings will continue from interest or investment returns.
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How Many ISAs Can I Use?
There is no limit to how many ISA accounts you can have open simultaneously. But that does not mean you can save unlimited amounts. The annual ISA allowance for 2026/27 is £20,000 across all your ISAs. That is the ceiling, no matter how many accounts you hold.
So yes, you could technically open multiple Cash ISAs, a Stocks and Shares ISA, and an Innovative Finance ISA in the same year. You can open and pay into more than one ISA of the same type in the same tax year, as long as your total ISA contributions stay within the £20,000 annual limit.
Two exceptions apply:
- You can hold multiple Lifetime ISAs, but you can only pay into one per tax year.
- Children can only hold one Junior Cash ISA and one Junior Stocks and Shares ISA each.
One practical thing to note: not all ISA providers allow you to open multiple accounts with them, so always check directly with your bank before applying.
How Does the ISA Allowance Work?
In the 2026/2027 tax year, the maximum you can save in ISAs is £20,000. This resets every year on 6 April — and whatever you don’t use by 5 April is gone. You cannot carry it forward.
Any money you save within that allowance is fully sheltered from income tax and capital gains tax, for as long as it stays in the ISA.
You can split the £20,000 across different ISA types, however you like — or put it all into one. The tax year runs from 6 April to 5 April.
What about withdrawals?
You can take your money out of an ISA at any time, without losing any tax benefits. But here is where most people get caught out.
If your ISA is flexible, withdrawing money and putting it back in the same tax year does not count against your allowance. If your ISA is not flexible, only the remaining allowance applies — the withdrawn amount does not come back. Always check with your provider which type you hold.
What are the Advantages of ISAs?
ISAs are one of the most straightforward tax-saving options available to UK residents. Here is why they matter.
No tax on your returns
You pay no income tax on interest or dividends earned within an ISA, and any profits from investments are free of capital gains tax. Whatever your money earns inside the ISA wrapper, HMRC cannot touch it.Â
No need to declare it
ISA income is not taxable, so it does not count towards your personal savings allowance or dividend allowance — and you do not need to tell HMRC about it. No extra paperwork, no self-assessment entries for ISA income.
Your savings stay protected indefinitely
If you deposit cash in time, you can keep it in there, tax-free, for as long as you like. The tax-free status does not expire when the tax year ends.
Withdraw anytime without penalty
There are no tax implications when taking money out of an ISA — you will not have to worry about paying tax on interest or growth, and you won’t need to declare ISA withdrawals to HMRC.
Couples can double the benefit
Each adult has their own £20,000 allowance. A couple investing together can shelter a combined (£20,000 + £20,000 ) = £40,000 per year completely tax-free.
Dividend tax is rising — ISAs shield you from it
In the 2026/27 tax year, the tax rate on dividends will rise to 10.75% for basic rate taxpayers and 35.75% for higher rate taxpayers. Holding stocks and shares inside an ISA means none of that applies to you.
How TAJ Accountants Help You Make the Most of Your ISA Allowance
When it comes to your savings and tax position, you need an accountant you can rely on — not just at year-end, but all year round.
At TAJ Accountants, we help you do exactly that.
- ISA and tax planning — We look at your full financial picture and advise on how to use your ISA allowance in a way that genuinely reduces your tax bill.
- Capital gains tax planning — If you hold investments outside an ISA, we help you manage and minimise CGT exposure before it becomes a problem.
- Self Assessment support — We make sure you are reporting correctly, claiming everything you are entitled to, and never overpaying tax.
- MTD compliance — As Making Tax Digital expands, we keep your records fully compliant using HMRC-approved software, including QuickBooks, Xero, and FreshBooks.
- Bookkeeping and record keeping — Accurate, up-to-date records mean no last-minute scrambles and no nasty surprises from HMRC.
Whether you are an individual saver, a sole trader, or a growing limited company, TAJ Accountants, your trusted partner as small business accountants, is here to help you keep more of what you earn.Â
Most people leave their ISA allowance underused and their tax position unreviewed — simply because they never got the right advice.
Conclusion
The ISA allowance is one of the simplest ways to grow your money without paying tax on it. But it is strictly use it or lose it — any unused allowance disappears permanently and cannot roll over to the next tax year.
And with the Cash ISA limit dropping to £12,000 from April 2027 for under-65s, this is your last year to deposit the full £20,000 into a Cash ISA.
Not sure where to start? Book a free consultation today and make sure you do not miss your ISA allowance.
