Glossary · UK
What is ISA?
Individual Savings Account — a tax-free wrapper for cash savings or investments.
Full Definition
An ISA (Individual Savings Account) is a tax-free wrapper that protects your savings or investments from Income Tax, dividend tax and Capital Gains Tax. The annual ISA allowance for 2025/26 is £20,000, which you can split across Cash ISAs, Stocks & Shares ISAs, Innovative Finance ISAs and a Lifetime ISA (up to £4,000). Junior ISAs for under-18s have a separate £9,000 allowance. ISAs were introduced in 1999. Once money is in an ISA, all returns are tax-free for as long as it stays there — no need to declare them on your tax return.
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Disclaimer: Definitions are for guidance only. For decisions about your tax, savings, property or pension situation, always consult a qualified professional or refer to gov.uk.