7 smart ways to use your ISA allowance

Every UK adult gets a £20,000 ISA allowance each tax year. No tax on interest, no tax on growth, no tax on dividends. It’s one of the most straightforward financial benefits available and yet a surprising number of people either ignore it, leave it until the last minute or simply park everything in a cash account without giving it much further thought.

A new tax year has just begun, which makes this the ideal time to think about how you’re going to use yours. Here are seven smart ways to make the most of what’s available.

1. Get it sorted now rather than later

The single most common ISA mistake is leaving it until the end of the tax year. People intend to sort it out and then suddenly it’s March and the pressure is on. Rushed decisions tend to be poor ones and missed deadlines mean a lost allowance you can never get back.

Why acting early actually makes a difference

Putting money into your ISA now rather than next spring gives it a full twelve months to grow. Do that consistently over a number of years and the timing difference alone becomes meaningful. With the new tax year having just started, you’re in the best possible position to make the most of your £20,000 allowance before life gets in the way.

2. Ask yourself whether cash is actually working for you

A Cash ISA has its place, particularly for money you might need at short notice. But if you’re saving for something further down the line, leaving it all in cash is often just the comfortable choice rather than the right one.

A big rule change is coming in 2027

From April 2027, under-65s won’t be able to put more than £12,000 a year into a Cash ISA. Your full £20,000 allowance still exists, but nearly half of it will effectively need to go into investments going forward. Those aged 65 and over keep the full cash limit as it stands today. It’s a clear government push towards encouraging people to invest rather than save in cash.

For longer-term money, a Stocks and Shares ISA is worth exploring:

• Over the long term, diversified investments have historically outperformed cash
• Values can go down as well as up, so it’s not suitable for everyone
• Getting advice before making the switch is sensible, particularly with larger sums

3. The lifetime ISA is underused and worth knowing about

If you’re between 18 and 39, the Lifetime ISA offers a 25% government bonus on contributions of up to £4,000 per year. That’s up to £1,000 of free money annually, which is genuinely hard to match anywhere else.

What you can use it for

• Buying your first home, on a property worth up to £450,000
• Retirement savings, which you can access from age 60

Withdrawing for any other reason currently triggers a penalty that costs you more than just the bonus, so it’s best suited to people who have a clear purpose for the money. It’s also worth knowing that the government has signalled it may replace the Lifetime ISA with a new first-time buyer product from 2028, so it’s an area to keep an eye on if it forms part of your planning.

4. Don’t forget the Junior ISA allowance

Parents and grandparents can contribute up to £9,000 per year into a Junior ISA on behalf of a child under 18. It sits entirely separately from your own £20,000 allowance, so it’s genuinely additional tax-free capacity.

The case for starting early

• All growth is free from income tax and capital gains tax
• The child can’t access the money until they turn 18, at which point it converts automatically into an adult ISA
• Time is the biggest advantage here. A child has potentially 18 years of compound growth ahead of them

Consistent contributions made from an early age could build into a significant pot by the time they reach adulthood, whether that’s used for a house deposit, university costs or simply a strong financial start.

5. You can split your allowance across multiple ISAs

Since April 2024, you can contribute to more than one ISA of the same type in a single tax year, as long as your total stays within £20,000. It’s a relatively recent change that gives people far more flexibility than before.

A straightforward example

Rather than putting everything into one account, you might consider:

• £5,000 in an easy-access Cash ISA for short-term needs
• £4,000 into a Lifetime ISA to claim the government bonus
• £11,000 into a Stocks and Shares ISA for long-term growth

Different pots, different purposes, all within the same annual allowance.

6. Use your ISA to protect gains from capital gains tax

If you hold investments outside an ISA and sell them at a profit, you may face a Capital Gains Tax bill on anything above your annual exempt amount. That exempt amount is now just £3,000 for 2026/27, down sharply from where it stood just a few years ago.

What this means in practice

• Higher and additional rate taxpayers pay 24% CGT on most gains above the threshold
• Inside an ISA, every penny of growth is completely free from CGT, no matter how large the gain
• The longer you hold investments inside an ISA, the more valuable that protection becomes

For anyone with a growing investment portfolio, sheltering assets within an ISA is one of the more practical tax planning steps that’s available to you.

7. If you’re a couple, plan your allowances together

Couples can each use their own £20,000 allowance, giving them up to £40,000 of combined tax-free capacity every year. Co-ordinating this as part of a shared financial plan is one of the simplest ways to improve overall tax efficiency.

The additional permitted subscription

There’s also a provision called the Additional Permitted Subscription (APS), which allows a surviving spouse or civil partner to inherit the ISA allowance their partner built up over a lifetime, even if they don’t directly inherit the funds themselves. It’s a detail that rarely gets discussed but can make a real difference in later life planning.

The ISA allowance is one of the best tools available to UK savers and investors. Used well, it can shelter decades of growth from tax and sit at the centre of a sound, long-term financial plan.

At Fairview, we’re independent financial advisers working with clients across the county. Contact us to talk about how to make the most of your ISA allowance as part of your wider financial plan.

Taxation, including inheritance tax planning is not regulated by the Financial Conduct Authority.

An ISA is a medium to long term investment, which aims to increase the value of the money you invest for growth or income or both. The value of your investments and any income from them can fall as well as rise. You may not get back the amount you invested.