Cash ISA vs stocks and shares ISA – what’s the difference?

Thinking about opening an ISA, but can’t decide between a cash ISA and a stocks and shares ISA? We explain the difference so you can decide what’s right for you.

What is a cash ISA?

A cash ISA is similar to a savings account, but the interest you earn is tax free.

Currently, you can pay up to £20,000 into a cash ISA each tax year. From April 2027, the annual cash ISA limit will be £12,000. Those aged 65 or over will still have the full £20,000 allowance.

With a fixed-rate cash ISA, the interest rate stays the same for a certain period of time. This could be from one to five years, for example. If you take your money out before the period is up, you might have to pay a charge.

With a variable-rate ISA, the interest rate can fluctuate. For example, if the Bank of England’s base rate goes down, the interest rate on a variable-rate ISA could go down too. You can take out money whenever you want to without paying a charge.

What is a stocks and shares ISA?

A stocks and shares ISA allows you to invest in a range of assets, including individual shares and bonds¹ and funds investing in shares and bonds². You can invest up to £20,000 each tax year and any returns are tax free.

What are the differences between a cash ISA and a stocks and shares ISA?

Both cash ISAs and stocks and shares ISAs are tax‑efficient ways to save or invest, but they work in very different ways.

A cash ISA works like a savings account, which means the amount you’ve saved won’t go down. Only the amount of interest that your money earns can change, so there’s very little risk. However, inflation can reduce the value of your money, which means it may not go as far in years to come.

With a stocks and shares ISA, your money is invested. This means your balance can change every day. You may even get back less than you put in.

But while a stocks and shares ISA carries more risk than a cash ISA, you can make much higher returns in the long term.

Shares beat cash over time

It’s important to know that cash is not a risk-free option. Its value can be eroded by inflation, which means your money could buy you a lot less in the future than it can today.

Historically, shares have delivered a higher return than cash over long periods.

The chart below compares the value of £10,000 saved in a bank account and invested globally since the end of December 2004, both before and after inflation.

If you put the money in a bank account, it would grow to around £15,600. But inflation means its real value reduces to around £4,100.

However, if you invested it globally in shares, it would grow to around £86,400 and be worth around £74,000 after inflation.

Returns from £10,000 in cash and shares, before and after the effects of inflation

Past performance is not a reliable indicator of future results. The performance of an index is not an exact representation of any particular investment, as you cannot invest directly in an index.

Notes: Cash returns represented by the UK Sterling Overnight Index Average benchmark (SONIA), which reflects the average rate of interest banks pay to borrow overnight. Global shares represented by the FTSE All-World Index with dividends reinvested. Inflation represented by the UK Retail Price Index (RPI).

Source: Factset, Vanguard calculations based on period 31 December 2004 to 31 December 2025.

Can I have both a cash ISA and a stocks and shares ISA in the same tax year?

You can have multiple cash ISAs and stocks and shares ISAs in the same tax year. And they can be with different providers.

However, the total amount you pay into all your ISAs in one tax year can’t be more than the £20,000 annual allowance.

Can I transfer a cash ISA to a stocks and shares ISA?

You can transfer a cash ISA into a stocks and shares ISA.

It’s important not to take the money out of your cash ISA and add it to your stocks and shares ISA. This is because it will use up some or all of your current year’s ISA allowance. Instead, make sure you do the transfer through your stocks and shares ISA provider. This won’t affect your annual allowance.

Some providers may charge exit fees, so check beforehand.

Can I transfer a stocks and shares ISA to a cash ISA?

You can currently transfer a stocks and shares ISA to a cash ISA. However, from April 2027, you will not be allowed to if you’re under 65.

Make sure you do the transfer through your cash ISA provider so it doesn’t affect your annual allowance.

Some providers may charge exit fees, so check beforehand.

Which is better – a cash ISA or a stocks and shares ISA?

The right type of ISA for you depends largely on what you’re saving for and when you’ll need the money.

If you’re saving for a short-term goal, like a holiday in a couple of years’ time, a cash ISA may be a better fit. This is because your money isn’t exposed to stock market ups and downs, so your balance won’t fall just before you need to use it. A cash ISA could also be a good option for your emergency fund – money set aside for unexpected costs – but only if it’s an easy-access ISA.

If you’re saving for the long term, a stocks and shares ISA gives your money the opportunity to grow over time. Investing over longer periods can help smooth out short‑term market movements and increase the chance of achieving your goals.

¹ Bonds are a type of loan issued by governments or companies, which typically pay a fixed amount of interest and return the capital at the end of the term.

² At Vanguard you can only invest in funds, not individual shares and bonds.

Investment risk information

The value of investments, and the income from them, may fall or rise and investors may get back less than they invested.

The eligibility to invest in either ISA or Junior ISA depends on individual circumstances and all tax rules may change in future.

Any tax reliefs referred to are those available under current legislation, which may change, and their availability and value will depend on your individual circumstances. If you have questions relating to your specific tax situation, please contact your tax adviser.

Your transfer will be sent to us as cash or shares (Vanguard funds only). During the transfer period any cash will not be invested so you could miss out on any increase in the value of your investments should the market rise.

Important information

Vanguard only gives information on products and services and does not give investment advice based on individual circumstances. If you have any questions related to your investment decision or the suitability or appropriateness for you of the product[s] described, please contact your financial adviser.

This is designed for use by, and is directed only at, persons resident in the UK.

The information contained herein is not to be regarded as an offer to buy or sell or the solicitation of any offer to buy or sell securities in any jurisdiction where such an offer or solicitation is against the law, or to anyone to whom it is unlawful to make such an offer or solicitation, or if the person making the offer or solicitation is not qualified to do so. The information does not constitute legal, tax, or investment advice. You must not, therefore, rely on it when making any investment decisions.

Issued by Vanguard Asset Management Limited, which is authorised and regulated in the UK by the Financial Conduct Authority.

© 2026 Vanguard Asset Management Limited. All rights reserved.

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