Individual Savings Accounts (ISAs) let you save or invest without paying tax on the returns. With an annual allowance of £20,000 across all ISA types, they are one of the most accessible tax-efficient savings vehicles available in the UK.
Key takeaways
- The annual ISA allowance is £20,000 across all ISA types
- ISA returns are completely tax-free — no income tax, capital gains tax, or dividend tax
- The allowance is use-it-or-lose-it each tax year
- ISAs offer flexible access, unlike pensions which are locked until age 55 (57 from 2028)
- Using both ISAs and pensions together provides tax diversification in retirement
Types of ISA
There are several types of ISA, each designed for different purposes:
- Cash ISA — Works like a savings account but interest is tax-free. Available from age 18.
- Stocks and Shares ISA — Allows you to invest in funds, shares, and bonds with no tax on capital gains or dividends within the ISA wrapper. Available from age 18.
- Lifetime ISA (LISA) — For people aged 18-39. Receive a 25% government bonus (up to £1,000/year) on contributions up to £4,000/year. Can be used for a first home or retirement after age 60. Penalties apply for other withdrawals.
- Innovative Finance ISA — Allows peer-to-peer lending within an ISA wrapper. Carries higher risk than Cash ISAs.
- Junior ISA — For children under 18, with a separate allowance of £9,000/year. The child gains access at age 18.
The ISA Allowance
Each tax year (6 April to 5 April), you can put up to £20,000 across your ISA accounts. This total is shared across all ISA types (except Junior ISAs, which have their own separate allowance).
The Lifetime ISA has a sub-limit of £4,000, which counts towards your £20,000 total.
Your ISA allowance is "use it or lose it" — you cannot carry forward unused allowance from previous years. However, money already in your ISA from previous years does not count against this year's allowance.
ISA vs Pension: Key Differences
Both ISAs and pensions offer tax advantages, but they work differently:
| Feature | ISA | Pension |
|---|---|---|
| Tax relief on contributions | No | Yes (20-45%) |
| Tax on withdrawals | No | Yes (income tax) |
| Access | Anytime | Usually from age 55 (57 from 2028) |
| Annual limit | £20,000 | £60,000 |
| Inheritance tax | Usually part of estate | Usually outside estate |
Many people use both: pensions for long-term retirement saving (benefiting from upfront tax relief) and ISAs for medium-term goals or as a flexible complement to their pension. Our financial planning tools can help you model the best split for your circumstances.
Transferring ISAs
You can transfer ISAs between providers without affecting your annual allowance. When transferring, use the official ISA transfer process rather than withdrawing and re-depositing, as withdrawals from a current-year ISA would use up that year's allowance if re-contributed.
Transfers from Cash ISA to Stocks and Shares ISA (and vice versa) are allowed. If you are uncertain about the best approach, you can find a regulated adviser to guide you.
Video: Recent Changes to the Cash ISA
ISA rules are not static — the cash ISA regime in particular has seen meaningful reforms. UK personal finance creator Damien Talks Money summarises what changed with the £20,000 cash ISA limit and the knock-on effects for savers:
Video credit: Damien Talks Money, independent UK personal finance creator. Wealth365 is not affiliated with the channel and shares this third-party content for general education only — it is not personal financial advice.
Important: This guide is for general educational purposes only and does not constitute financial advice. Tax rules can change and individual circumstances vary. If you need advice tailored to your situation, please consult a qualified, FCA-regulated financial adviser. You can browse advisers in our adviser directory.