Everyone over the age of 18 in the UK can start investing into the greatest wealth-building tool of all time, the stock market. And you have access to fantastic tax-sheltered accounts like an ISA. Let’s take Bob, who’s been investing into an ISA for 20 years, from age 20 to age 40. He now has £1.18 million and will be able to retire*, and the gains he’s made are completely tax-free. He doesn’t have to pay a single penny of tax. Nothing. Pretty incredible. In this blog, we’ll investigate how you can also make the most of your ISA allowance, and grow your wealth into something amazing inside these tax sheltered accounts.
ISA vs Pension
I initially wanted this blog to be a comparison of ISAs and pensions. Which is better? Well, it turns out there is already a lot of information out there on this topic (just search “pension vs ISA” in Google). No point in me regurgitating it all. (If you are interested in this topic, I recommend you read Vanguard’s article, which summarises everything in a succinct manner.)
There is no simple answer to which is better. They both offer tax-free sheltering for your money, while the government will top up your pension by 20% (or 40% or more if you’re a higher-rate tax payer – although you’ll need to complete a self-assessment tax return to get them to do this) – so your money is paid gross (before tax) into a pension. You do have to pay tax when you withdraw money from a pension, but not from an ISA. For a lot of people, the crunch point comes with the accessibility; you can access money in an ISA whenever you want, but for a pension, you need to be at least age 55 (or 57 after April 2028).
For us folk who have discovered the power of compound interest and cutting our expenses, a pension is no good. We want to retire early – 10, 20, even 25 years early – so we need a decent stash of cash in an ISA – at least enough to get us through to when we can access the pension. So, ultimately, it really depends on what your goal is. If it’s early retirement, then you won’t want to focus too heavily on maximising pension contributions.
ISA summary
There are a few different flavours of ISA. The Cash ISA is vanilla flavour (with the scoops soon to be made smaller, see below), the Stocks and Shares ISA is more interesting strawberry flavour (my favourite), while the Lifetime ISA and Innovative Finance ISA are more exotic (and not for everyone).
Note that from 6th April 2027, new rules will come into effect: cash ISA contributions for under-65s will be capped at £12,000 per year, but the normal £20,000 limit will still be available for other ISAs.
Investing Pillars
First, we need to make sure we’ve covered the standard investing pillars. Make sure you’re investing into a broad-based index fund that tracks an entire stock market, and ensure the fees are low, probably by investing with Vanguard.
Flavours of ISA
The Lifetime ISA and the Stocks and Shares ISAs are the two flavours which allow you to invest. Of course, you can choose to invest your money however you want – you could stock pick or buy Bitcoin if you want (hint: don’t buy Bitcoin, it’s not an investment), but unless you’re Warren Buffet, and you’re probably not, it’s extremely unlikely you’ll beat the market doing this. Buy index funds instead.
Lifetime ISA
The Lifetime ISA is the best ISA for investing, as the government will give you a 25% top up to your contributions (although there’s a £4000 per year contribution limit). So, that’s an immediate 25% return on your contributions – before any investment growth.
Personally, I like being able to access my money when I want, and I also like Vanguard – so I don’t currently have a Lifetime ISA (although I have done in the past). This may change in the future, however.
Stocks and Shares ISA
If you want access to your money before retirement, in a tax-sheltered account, invest as much money as you can each year into a Stocks and Shares ISA, up to the £20k limit. Invest a certain percentage of your income (more than 50% if you want to retire early) into it every month. This employs pound-cost averaging, which smooths the short-term market volatility on your portfolio.
If you have a large lump-sum to invest, say from an inheritance or bonus, research suggests it’s best to invest it all at once, rather than drip-feeding the money in over a period of time. At this point, you have to balance what the maths suggests with how comfortable you feel emotionally investing a large sum all at once. This is not as easy as it sounds. What would you do if the market suddenly crashed after you invested a large amount of money?
Make the most of it!
If you want to achieve early retirement, then I suggest concentrating heavily on ISA investments. Max out your workplace pension contribution up to the company match, but no more. Scoop whatever money you have left over after this each month into a Stocks and Shares ISA.
A Stocks and Shares ISA is the perfect vessel for building wealth, with absolutely ZERO tax to pay when you sell your investments many years or decades from now – which will have no doubt increased in value many times over by then.
Bob and Joe
Let’s go back to the beginning of this article and Bob, who’s become an ISA millionaire in 20 years. He doesn’t even have to worry about paying tax when he sells his investments. But Bob’s cousin, Joe wasn’t so clever. He still managed to save and invest aggressively, also amassing £1.18 million after 20 years – but none of this is in an ISA. He now has to pay 18% tax (Capital Gains Tax) on the gains in his investments when he withdraws between £12,570 and £50,270 per year, and 24% on any gains above this threshold.
These retirement portfolios will have had decades of market exposure by the time the money is withdrawn, meaning that the majority of the portfolio is composed of market gains rather than the principal amount invested. A huge amount of tax will need to be paid by Joe every time he withdraws money. The long-term tax implications of not investing in an ISA are enormous.
Don’t worry, be happy!
Understanding ISAs might not be the most exciting topic, but it’s certainly stuff you need to know. Master the basics of investing and tax sheltered accounts and put your investing on autopilot. Then forget about it; the less worrying you give your money, the better it will do in the long-term.
Now get back to a happy, healthy life of hard work, lifting weights and intentional living, as you continually strive to be the best version of yourself!
FAQ
Aim to invest as much of the £20,000 annual limit as possible, ideally throughout the year using pound-cost averaging. Prioritise a Stocks and Shares ISA for long-term growth, and avoid withdrawing funds unnecessarily, as this can reduce the tax-free compounding benefits over time.
Withdrawing money from an ISA reduces the amount benefiting from tax-free growth. In most cases, you cannot replace those funds without using up more of your annual allowance (unless you have a flexible ISA). For long-term investing, it’s best to leave your money invested to maximise compounding over time.
The Slow Down and Save approach is to invest in low-cost, globally diversified index funds. These track the performance of the overall market and have very low fees – both of which help maximise long-term returns. Avoid frequent trading or stock picking unless you have strong expertise, as most investors underperform the market over time.
Both ISAs and pensions have advantages. ISAs offer flexibility, allowing you to withdraw funds at any time tax-free – making them ideal for early retirement. Pensions provide upfront tax relief but restrict access to later in life (age 57 from April 2028). Which is best for you depends on your goals and personal preferences.
The standard ISA allowance is £20,000 per tax year, which can be split across different types of ISA. The Lifetime ISA has its own £4,000 limit within this total. From April 2027, Cash ISA contributions for under-65s will be capped at £12,000 per year. Allowances reset each tax year, and unused allowances cannot be carried forward.
*This assumes Bob invests £20,000 per year (the current ISA limit) into the global stock market at a 9% annual average return. A perfect storm for compound growth, especially with no fees assumed. But then again, if you’re investing with Vanguard, the fees will be minimal.
Curious for more? You might like the following:
- A no-nonsense guide on how to live a healthy life
- The best routine for your pay check
- Why you need to consume less
- How to get ahead with money
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