ISAs Explained
An ISA is a tax-free wrapper for your savings and investments. These guides cover the allowance, the different types and the rules that catch people out.
- ISAs Explained: How ISAs Work in 2026/27How ISAs work in the 2026/27 tax year: the £20,000 allowance, the four types of adult ISA, Junior ISAs, withdrawals, transfers and the 2027 cash ISA change. Updated 10 October 2026.
- ISA Allowance 2026/27: Rules and ChangesThe 2026/27 ISA allowance explained: how much you can pay in, what counts towards it, paying in too much, and the cash ISA limit change from April 2027. Updated 10 October 2026.
- Stocks and Shares ISA vs Cash ISAHow a stocks and shares ISA differs from a cash ISA: risk, returns, access, FSCS protection, the 2026/27 allowance and the cash ISA change coming in April 2027. Updated 10 October 2026.
- Lifetime ISA Explained: Bonus and RulesHow the Lifetime ISA works in 2026/27: who can open one, the 25% bonus, the first-home rules, the 25% withdrawal charge and the planned First Time Buyer ISA. Updated 10 October 2026.
- Junior ISAs Explained: 2026/27 GuideHow Junior ISAs work in 2026/27: the £9,000 limit, cash or stocks and shares, who can pay in, what happens at 16 and 18, Child Trust Funds and the tax rules. Updated 10 October 2026.
The allowance in one sentence
In the 2026/27 tax year you can pay up to £20,000 into ISAs in total, split however you like across cash, stocks and shares, innovative finance and Lifetime ISAs, and any allowance you don't use by 5 April is lost. Growth inside an ISA doesn't count towards the allowance. Our ISA guide covers the full rules, including Lifetime and Junior ISAs.
The rules that catch people out
Withdrawing money from a normal ISA and paying it back in uses up allowance again unless the ISA is flexible. Moving an ISA by withdrawing it yourself loses its tax-free status, so transfers should always go through the new provider. And Lifetime ISA withdrawals for anything other than a first home, age 60 or terminal illness carry a 25% charge, which takes back more than the bonus.
What changes in April 2027
From 6 April 2027 the annual cash ISA limit falls to £12,000 for people under 65, under regulations laid before Parliament on 14 September 2026. The overall £20,000 allowance stays the same, so under-65s will still be able to put the other £8,000 into stocks and shares or other ISA types. The 2026/27 rules are unchanged. Our guide to the ISA allowance explains the new rules, including limits on moving money from investments into cash.
Which type of ISA should you look at?
The type depends on what the money is for and when you'll need it. A cash ISA works like a savings account, with interest paid tax-free and no risk to the amount you put in from market falls. A stocks and shares ISA holds investments such as funds and shares. It suits money you can leave alone for years, and its value can fall as well as rise. A Lifetime ISA is for people aged 18 to 39 saving for a first home costing £450,000 or less, or for later life. It adds a 25% bonus on up to £4,000 a year; our Lifetime ISA guide covers the first-home rules and the withdrawal charge. Our comparison of stocks and shares ISAs and cash ISAs sets out the trade-offs side by side.
Junior ISAs for children
A Junior ISA is a separate tax-free account for a child under 18 who lives in the UK. Up to £9,000 can be paid in during 2026/27, and this doesn't use any of your own £20,000 allowance. A parent or guardian opens it, but the money belongs to the child. They can take control of the account at 16 and withdraw the money from 18. Our Junior ISA guide covers who can pay in, Child Trust Funds and the tax rules.
How to move an ISA without losing the tax benefits
Always ask the new provider to arrange the transfer for you. Withdrawing the money yourself and paying it in somewhere else loses its ISA status for good. According to GOV.UK, transfers between cash ISAs should take no more than 15 working days, and other transfers no more than 30 calendar days. Check whether your current provider charges an exit fee before you move.
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