From 6 April 2027, the total amount you can deposit in a tax-free cash ISA each year will be reduced to £12,000 if you are aged 65 or under. However, the total annual ISA allowance will remain at £20,000, which means that £8,000 of your allowance can be used exclusively for investments. You can still choose to use the entire £20,000 allowance in an investment ISA if you would like.

Remember, the new cash limit rule only applies to money being deposited after April 6 2027 and doesn’t affect any existing money in your ISA accounts. This means you have over a year to consider your options and learn more about investing, and how different types of ISA work. The ISA rules will not change if you are over 65.

What’s the difference between a cash ISA and an investment ISA? 
 

A cash ISA allows you to save your money and earn interest tax free, year after year. An investment ISA allows you to make investments, where any returns, dividends and interest are all tax free. However, your money is at risk. The value of investments can go up or down, and you may get back less than you invest.

What’s the difference between a Stocks & Shares ISA and an Innovative Finance ISA?  


A Stocks & Shares ISA and an Innovative Finance ISA are both different types of investment ISA. The Stocks & Shares ISA is the most common and allows you to invest in stocks, shares, funds and bonds.  

An Innovative Finance ISA allows you to invest in crowdfunding offers and peer-to-peer loans. These investments often carry higher levels of risk than the investments held in a Stocks & Shares ISA.  

Your investment strategy under the new rule 


So, depending on your current situation, the new rule may have different impacts on what you do with your money. We’ve put together some different scenarios below to help explain how the rules could work in practice. This information is for general guidance only and does not constitute financial advice. If you are unsure whether investing is right for you, you may wish to seek independent financial advice. Remember, all of these scenarios only apply to you if you are aged 65 or under, and when the rules come into place on 6 April 2027.

“I already use an investment ISA”

Great! If you regularly use your whole ISA allowance in your Investment ISA, then there’s nothing more you need to do. Remember, with a Triodos Stocks & Shares ISA or Innovative Finance ISA, you can spread your investments across different funds or projects if you want to.

“I use both a cash ISA and an investment ISA”  

You will only be able to deposit up to £12,000 in your cash ISA once the new rules start in April 2027, but you can use as much of your £20,000 allowance as you like in a Stocks & Shares or Innovative Finance ISA. So, you can put £12,000 in your cash ISA and £8,000 in a Stocks & Shares or Innovative Finance ISA or you can spread your allowance more evenly between them, putting £10,000 in cash and £10,000 in investments, for example.  

Remember to assess the amount of risk you’re willing to take if you’re considering increasing the amount of money you invest. If you need to build an emergency fund or are saving money you’ll need to use in the short term (under five years), you should consider a non-ISA savings account after you’ve reached the £12,000 limit for your cash ISA.

“I invest already, but not in an ISA”

If you usually put £20,000 in your cash ISA, but invest in investments outside of an investment ISA, this is a great opportunity to begin investing in a tax-efficient account. You will only be able to deposit up to £12,000 in your cash ISA, so if you want to use the full £12,000, you can then use your remaining £8,000 in a Stocks & Shares or Innovative Finance ISA.

“I’ve never invested before” 

Just because £8,000 of your ISA allowance is reserved for investments, that doesn’t mean you have to use it all – you can invest any amount up to the £20,000, which could be as little as £25 a month in a Triodos Stocks & Shares ISA. If you’re just getting started with investing, you can deposit smaller amounts whilst you learn and become more comfortable with investing.  

If you’re not comfortable with risk, or need to focus on saving, then you can use your £12,000 cash ISA limit and then continue to save in a non-ISA savings account.  

If you’d like to consider investing and want to learn more, we’ve shared some further information in articles below. Always seek help from a financial advisor if you aren’t confident making decisions about your money.  

Learn more about investing   

Browse our investment topics below:  
Is investing right for me? | Triodos Bank 
Choosing Impact Investment funds | Triodos Bank 
Five ways to help understand impact investment risk | Triodos Bank 
Triodos launches investment calculator

When you invest, your money is at risk

Investing is not the same as putting your money into a savings account – your money is at risk. Investments go up and down in value over time, so you could get back less than you originally invested. Investments should be held for the long term (five years or more). If you’re investing with an ISA, remember that any tax benefits will depend on your circumstances and that rules can change over time.  

Investments are not covered by the Financial Services Compensation Scheme.  

This information was correct at the time of publication - (27 January 2026). ISA rules are subject to change and you should always check the most up to date information.