Share your opinion and earn yourself a free Motley Fool premium report!

We are looking for Fools to join a 75 minute online independent market research forum on 15th / 16th December.

To find out more and express your interest please click here

How investing £300 a month in the FTSE 100 could help you retire a millionaire!

I believe that by saving and investing regularly in FTSE 100 (INDEXFTSE:UKX) shares, it’s possibly to retire a millionaire.

The content of this article was relevant at the time of publishing. Circumstances change continuously and caution should therefore be exercised when relying upon any content contained within this article.

You’re reading a free article with opinions that may differ from The Motley Fool’s Premium Investing Services. Become a Motley Fool member today to get instant access to our top analyst recommendations, in-depth research, investing resources, and more. Learn More.

Many of my friends ask me if it’s possible that they could retire as millionaires. My simple answer is, yes. Even on a minimal income level, I believe people can become millionaires by retirement age if they start early enough. 

How is that possible?” they understandably ask. I reply that it’s through investing regularly and the magic of compounding returns. Let’s take a closer look.

Compounding returns

Let’s assume that you’re 25 years old with only £100 in savings and that you plan to retire at age 65. You invest that £100 and earn an 8% annual return. Then you make an additional £3,600 of contributions annually at the start of each year.

You have 40 years to invest. The annual return is 8%, compounded once a year. At the end of 40 years, the total amount saved becomes £1,009,384!

Saving £3,600 a year would mean being able to put aside about £300 a month or about £10 a day. Might you just be wondering if you should skip that next impulse purchase?

Investing later in life?

On the other hand, if you wait to start investing until you’re 30, you will have ‘only’ £671,446. The difference is due to the power of compound interest. This has a snowball effect on personal savings. As time goes on, interest leads to more money, over and over again. 

In other words, if you start saving later in life, you have to save more each year in order to make up the difference. For example, if you start investing at age 40, then you would need to save and invest slightly over £1,000 a month to reach a million in your retirement account by age 65.

Ensuring a financially secure retirement

The full basic state pension is currently £168.60 per week. Do you truly believe you can live on that amount for the rest of your life after retirement? 

It’s important to have a realistic view of how you can pay for a retirement of several decades. For example, I’d encourage you to contribute to your workplace pension scheme if you have one.

Every UK resident should also learn more about the different types of ISAs available to them, with an emphasis on Stocks and Shares ISAs. 

My Motley Fool colleagues regularly cover FTSE 100 and FTSE 250 shares, as well as funds to consider adding to a diversified retirement portfolio. They point out that the stock market returns about 7% to 9% annually on average. 

FTSE investment options

The FTSE 100 seems to be the initial index Britons mostly consider when they first start investing. It’s composed of the 100 largest companies, by market capitalisation, on the London Stock Exchange (LSE). The FTSE 250 is the next 250 largest companies and also has a number of investment trusts. 

As you start learning more about the investment choices available, you’re likely to feel that some companies may be more appropriate for novice investors.

You may, for example, want to initially stay with large-cap shares as well as those with high (but reliable) dividend yields. Any capital gains delivered by the stock would be an added bonus on top of the dividend.

Another option could be to invest in low-cost exchange-traded funds (ETFs), which track popular stock indices both in the UK and globally. For example, if you’re interested in dividend stocks, then the iShares UK Dividend UCITS ETF may be an ETF to consider.

tezcang has no position in any of the shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool we believe that considering a diverse range of insights makes us better investors.

More on Investing Articles

Light trails from traffic moving down The Mound in central Edinburgh, Scotland during December
Investing Articles

Start investing this month for £5 a day? Here’s how!

Is a fiver a day enough to start investing in the stock market? Yes it is -- and our writer…

Read more »

Young mixed-race couple sat on the beach looking out over the sea
Investing Articles

Investing in high-yield dividend stocks isn’t the only way to compound returns in an ISA or SIPP and build wealth

Generous payouts from dividend stocks can be appealing. But another strategy can offer higher returns over the long run, says…

Read more »

Middle-aged white man wearing glasses, staring into space over the top of his laptop in a coffee shop
Investing Articles

A rare buying opportunity for a defensive FTSE 100 company?

A FTSE 100 stock just fell 5% in a day without anything changing in the underlying business. Is this the…

Read more »

Two elderly people relaxing in the summer sunshine Box Hill near Dorking Surrey England
Investing Articles

Simplify your investing life with this one key tip from Warren Buffett

Making moves in the stock market can be complicated. But as Warren Buffett points out, if you don’t want it…

Read more »

Tesco employee helping female customer
Investing Articles

Is Tesco a second income gem after its 12.9% dividend boost?

As a shareholder, our writer was happy to see Tesco raise dividends -- again. Is it finally a serious contender…

Read more »

Rolls-Royce Hydrogen Test Rig at Loughborough University
Investing Articles

Has the Rolls-Royce share price gone too far?

Stephen Wright breaks out the valuation models to see whether the Rolls-Royce share price might still be a bargain, even…

Read more »

Tŵr Mawr lighthouse (meaning "great tower" in Welsh), on Ynys Llanddwyn on Anglesey, Wales, marks the western entrance to the Menai Strait.
Investing Articles

How much do you need to invest in a FTSE 100 ETF for £1,000 monthly passive income?

Andrew Mackie tested whether a FTSE 100 ETF portfolio could deliver £1,000 a month in passive income – the results…

Read more »

Two business people sitting at cafe working on new project using laptop. Young businesswoman taking notes and businessman working on laptop computer.
Investing Articles

One of my top passive income stocks to consider for 2026 is…

This under-the-radar income stock has grown its dividend by over 370% in the last five years! And it might just…

Read more »