An Individual Savings Account (ISA) is the UK’s primary tax-efficient investment wrapper. Any returns earned inside an ISA — capital gains, dividends, or interest — are completely free from UK tax, with no need to declare them on your self-assessment return. For anyone investing in the UK, understanding ISAs is foundational before putting money to work in any taxable account.
What is the ISA allowance for 2026/27?
You can contribute up to £20,000 per tax year (6 April to 5 April) across all your ISAs combined. This allowance applies for the 2026/27 tax year. The allowance resets each tax year and cannot be carried forward: unused allowance is permanently lost at the end of the tax year. You can hold multiple types of ISA simultaneously but cannot exceed the £20,000 total limit across all of them in a single tax year.
What are the different types of ISA?
Cash ISA
A Cash ISA is a tax-free savings account that pays interest. Interest earned inside a Cash ISA is not subject to income tax, regardless of the amount. This is most useful when interest rates are relatively high — during periods of elevated Bank of England base rates, a competitive Cash ISA can offer meaningful returns without any tax liability.
Pros: Capital is protected (eligible deposits are covered by FSCS up to £85,000), no risk of loss, and returns are certain if held to a fixed term. Useful for emergency funds and money needed within 1–3 years.
Cons: Over longer periods, cash savings typically fail to keep pace with inflation. The real purchasing power of money held in a Cash ISA for 20 years will almost certainly be lower than if that money had been invested in equities, even accounting for market volatility.
Stocks and Shares ISA
A Stocks and Shares ISA allows you to hold shares, ETFs, investment trusts, bonds, and funds. All capital gains and dividend income generated inside the wrapper are completely free from UK tax — no CGT, no dividend tax, and no income tax on investment income. This is the most relevant ISA type for anyone building long-term wealth.
The tax saving inside a Stocks and Shares ISA compounds over time. For an investor holding a global equity ETF for 20–30 years, the accumulated CGT that would have been payable outside an ISA can easily exceed the original amount invested. For higher-rate taxpayers — who pay 24% CGT on investment gains and 33.75% dividend tax above the £500 allowance — the ISA wrapper is even more valuable.
Lifetime ISA (LISA)
Available to adults aged 18–39. You can contribute up to £4,000 per year and the government adds a 25% bonus on contributions — up to £1,000 per year. Contributions and the bonus grow tax-free inside the wrapper.
The important restriction: The LISA can only be used for two purposes without penalty — purchasing a first home (up to £450,000 purchase price) or retirement from age 60 onwards. Withdrawing for any other reason incurs a 25% penalty on the full withdrawal amount. Because the 25% penalty is applied to the full withdrawal (including the government bonus), not just the bonus itself, the effective penalty on your own contributions is greater than it initially appears. Withdrawing £5,000 (including £1,000 of government bonus) incurs a £1,250 penalty, leaving you with £3,750 — less than your original £4,000 contribution. The LISA is excellent for its intended purposes and poor for anything else.
Innovative Finance ISA (IFISA)
Allows tax-free returns from peer-to-peer lending and other alternative finance investments. The headline returns can appear attractive — some platforms advertise rates of 5–10%. The key difference from other ISA types is that the underlying loans are not covered by FSCS. If a borrower defaults and the platform cannot recover the loan, you lose that capital. The ISA wrapper makes the returns tax-free, but it does not protect the principal. IFISAs are not appropriate for most retail investors and are not recommended as a starting point.
Junior ISA (JISA)
Parents or guardians can open a Junior ISA for a child under 18. The annual allowance is £9,000 for 2026/27, completely separate from the adult ISA allowance. Grandparents, other relatives, and friends can contribute to the account, up to the annual limit.
The child cannot access the funds until they turn 18, at which point the JISA automatically converts to an adult ISA and the child gains full control. Interest, dividends, and capital gains inside a JISA are entirely tax-free. A Stocks and Shares JISA invested in a global equity ETF from birth, with regular monthly contributions, illustrates the power of long-term compounding: £200 per month for 18 years at 7% average annual return produces approximately £90,000 — built from £43,200 of contributions and roughly £47,000 of investment growth.
Why the ISA tax saving matters in practice
Without an ISA, investments held in a general investment account (GIA) are subject to two main taxes. Capital Gains Tax (CGT) applies to gains above the annual CGT exemption — £3,000 in 2025/26 and maintained at that level into 2026/27. Gains above the exemption are taxed at 18% (basic rate taxpayers) or 24% (higher rate taxpayers) for investment gains following the October 2024 Budget changes. Dividend income above £500 is taxed at 8.75% (basic rate) or 33.75% (higher rate).
The CGT annual exemption has been reduced significantly in recent years — it stood at £12,300 as recently as 2022/23. At £3,000, it now provides very limited shelter for any investor whose portfolio has grown meaningfully. For anyone with significant gains in a GIA, maximising ISA contributions each year to shelter future growth is a priority.
Unlike the United States, the UK does not have a “wash sale” rule — there is no restriction on selling an investment at a loss, claiming it against gains, and immediately buying the same investment back. For investors with taxable accounts, this creates legitimate “bed and ISA” planning opportunities: selling investments in a GIA, crystallising a loss or gain, and repurchasing the same investment inside an ISA to shelter future growth from further tax.
ISA vs. SIPP: which should you prioritise?
A Self-Invested Personal Pension (SIPP) is the other major UK tax wrapper for long-term investing. Contributions receive upfront income tax relief at your marginal rate: a basic-rate taxpayer contributing £800 receives £200 automatic tax relief from HMRC (making the effective cost £800 for a £1,000 pension contribution). A higher-rate taxpayer can claim an additional 20% relief through their tax return, making the effective cost £600 for a £1,000 contribution.
The trade-off is access. SIPP money cannot be withdrawn until age 55 (rising to 57 from 2028). This makes SIPPs ideal for retirement-specific savings and ISAs better for money you may need before retirement.
A commonly recommended approach for UK investors: contribute to a SIPP up to the level that maximises the higher-rate tax relief (i.e., ensuring pension contributions bring your taxable income to the basic-rate band), then direct additional long-term savings into a Stocks and Shares ISA. For most basic-rate taxpayers, the difference in tax relief between SIPPs and ISAs is less dramatic — the guaranteed 20% pension top-up is useful, but the ISA’s accessibility may make it more appropriate for savings that might be needed before age 55.
Which platforms offer Stocks and Shares ISAs?
All major UK investment platforms offer Stocks and Shares ISAs. The main considerations are platform fees, fund/ETF range, and usability:
- Vanguard Investor: Platform fee 0.15% per year, capped at £375. Commission-free for Vanguard’s own funds and ETFs. Best suited for investors who want to hold Vanguard ETFs or LifeStrategy funds exclusively. Limited fund range beyond Vanguard’s own products.
- Hargreaves Lansdown: Platform fee 0.45% tapering with portfolio size, capped at £45 per year for ETFs held in an ISA. Broadest range of funds and ETFs, strongest research tools, and the most established customer service of any UK platform. Higher fees make it less competitive for smaller portfolios.
- AJ Bell: Platform fee 0.25% tapering to 0.10% above £500,000. Good range of ETFs and funds at competitive cost. Solid for mid-to-large portfolios where Hargreaves Lansdown’s fees become significant.
- Freetrade: £5.99 per month for ISA access (as of 2025). Zero commission on all share and ETF trades. Best suited for investors making frequent small contributions who want to minimise per-trade costs. Narrower research tools but improving platform quality.
- InvestEngine: Zero platform fee for DIY ETF portfolios (commission-free ETF investing). Growing platform, FCA regulated, strong for pure ETF investing at minimal cost.
ISA transfers: moving between providers
You can transfer an ISA to a different provider at any time without losing the tax-free status of the funds or using up any of the current year’s allowance. The transfer must go directly between providers — withdrawing and redepositing counts as a new contribution against the annual allowance. Most providers accept in-kind transfers (investments move without being sold) and in-cash transfers (investments are sold and cash moves). In-kind transfers typically take two to four weeks.
Why putting investments in an ISA is almost always right
The case for the ISA is almost always the right one for UK long-term investors for a simple reason: the tax saving is guaranteed and permanent, while the cost is minimal (in many cases zero). An investor who fills their Stocks and Shares ISA allowance and holds a low-cost global equity ETF for 20 years will pay no CGT and no dividend tax on however much that investment grows. At current CGT rates, the tax that would have been payable in a GIA can easily represent a five- or six-figure sum on a mature portfolio.
The ISA also simplifies administration: no CGT calculations, no tax return entries for investment income, and no annual disposal decisions to keep gains under the CGT exemption. For the vast majority of UK retail investors, the Stocks and Shares ISA is the single most useful financial structure available.
Related reading
- ETFs and index funds: the beginner’s case for passive investing
- Investing vs trading: the key differences and which approach suits you
- Compound interest: how it works and why starting early matters
- How to choose a broker: the checks that matter before depositing
- Volatility: what it is, how it is measured, and why it matters
Frequently asked questions
Can I have multiple ISAs?
Yes. You can hold multiple ISAs of different types simultaneously — for example, a Cash ISA, a Stocks and Shares ISA, and a Lifetime ISA at the same time. However, from the 2024/25 tax year, HMRC permits subscribing to multiple ISAs of the same type in the same tax year (a rule change that removed the previous restriction of one new ISA per type per year). The overall £20,000 annual limit still applies across all ISAs combined. You cannot exceed £4,000 into a LISA in any tax year regardless of the overall allowance.
What happens to my ISA if I die?
Your ISA passes to your estate and may be subject to inheritance tax depending on the total estate value and applicable exemptions. However, your spouse or civil partner can inherit your ISA allowance through the Additional Permitted Subscription (APS) rule. This allows them to make an additional ISA subscription equal to the value of your ISA at the time of death, maintaining the tax-free wrapper on those assets rather than losing it on transfer. The APS must be used within three years of the account holder’s death or 180 days after the administration of the estate is complete, whichever is later.
Can I use my ISA for trading CFDs?
No. CFDs are derivatives, and ISA rules restrict holdings to qualifying investments — which include listed shares, ETFs, investment trusts, gilts, and regulated collective investment schemes. CFDs, spread bets, and other leveraged derivative products are not eligible to be held inside any ISA wrapper. Any profits from CFD trading are subject to CGT in a standard taxable account (though spread betting profits are CGT-exempt in the UK as they are classified as gambling). If you want tax-efficient exposure to financial markets, the ISA is the right wrapper — but for investing in conventional instruments, not for leveraged derivatives trading.
Can I withdraw money from a Stocks and Shares ISA?
Yes, from a standard flexible Stocks and Shares ISA, you can withdraw funds at any time without penalty. If your ISA is flexible (most modern ISAs are), you can also replace withdrawn amounts in the same tax year without using additional allowance. For example, if you have already contributed £20,000 and then withdraw £5,000, a flexible ISA allows you to re-contribute that £5,000 later in the same tax year. The Lifetime ISA is the significant exception — withdrawals before age 60 for non-qualifying purposes incur a 25% government penalty.
