Cash ISA vs Stocks and Shares ISA: Which Should You Pick?

A cash ISA keeps your money safe and pays interest tax-free, ideal for short-term goals. A stocks and shares ISA can grow more over time but can also fall in value. The right choice depends on your timeline and appetite for risk.

Last reviewed: 30 May 2026 · 2 min read

Key Facts

Both share the £20,000 annual ISA allowance for 2026/27
Cash ISAs currently pay up to around 4.75% AER
Stocks and shares ISAs carry risk but have higher long-term potential

When a cash ISA makes sense

A cash ISA works like a savings account where the interest is tax-free. Your money is protected up to £85,000 by the FSCS and the balance won't fall, so it's ideal for an emergency fund or anything you'll need within a few years. The best easy-access cash ISAs currently pay up to around 4.75%.

If you can't afford for your money to drop in value, or you'll need it soon, cash is the sensible home for it.

When a stocks and shares ISA makes sense

A stocks and shares ISA invests your money in funds, shares or bonds. Returns aren't guaranteed and the value can fall as well as rise, but over long periods investments have historically outpaced cash savings.

This suits money you won't touch for at least five years — anything shorter and a market dip could leave you worse off when you need to withdraw. The tax-free wrapper means no income or capital gains tax on what you make.

You don't have to choose just one

Since 2024 you can pay into both types in the same tax year, as long as your total stays within the £20,000 allowance. Many people keep an emergency fund in cash and invest longer-term money in a stocks and shares ISA.

From April 2027 there's a twist: the cash ISA limit drops to £12,000 a year for under-65s, with the rest of the allowance needing to go into investments. For now, though, you can still use the full £20,000 in cash.

FAQ

Frequently Asked Questions

Is a stocks and shares ISA worth it for a student? +

It can be, but only for money you won't need for at least five years. Investing while young gives your money the most time to grow. If you might need the cash sooner — for rent, fees or emergencies — a cash ISA or savings account is safer, since investments can fall in value short-term.

Can I move money from a cash ISA to a stocks and shares ISA? +

Yes, you can transfer between ISA types without losing your tax-free status, as long as you use the official ISA transfer process rather than withdrawing the money yourself. Withdrawing and re-depositing could use up your annual allowance again, so always ask your provider to transfer it directly.

Which ISA gives the best returns? +

Over the long term, stocks and shares ISAs have historically returned more than cash, but with no guarantee and the risk of falls. Cash ISAs give modest but certain returns. The 'best' depends entirely on how long you're saving for and whether you can tolerate ups and downs.

Topics covered

isas cash isa stocks and shares isa

This article is for informational purposes only and does not constitute financial advice. Always do your own research or speak to a qualified financial adviser before making financial decisions.