The number of people with £1,000,000 in a Stocks and Shares ISA just seems to keep going up. And I think that’s set to continue.

There are no shortcuts. But with time on your side, you might not need as much cash as you think to join the ranks of the ISA millionaires.

No savings at 40?

In a lot of ways, millennials have had things pretty good compared to our parents or grandparents. And I say this as one of them myself.

More of my cohort went to university than earlier generations. Travel is also much more accessible and things like Netflix exist.

Financially, though, things are tough. House prices have grown faster than wages, interest rates are low, and employment is less predictable.

Given all this, it’s easy to see how millennials might put off saving. But even getting started at 40, it’s not too late.

How much do you need?

The long-term average return from the FTSE 100 has been around 6.5% a year. And a 40-year-old in the UK qualifies for the State Pension in 28 years.

Working backwards, that’s enough to turn £171,300 into £1m by retirement. But that’s no good to someone starting from scratch.

The good news is that investing a fixed amount each month could achieve the same result. And the amount required is £1,053. For a lot of people, that might be a lot more realistic than £171,300 at the outset. The next question is what to invest in.

Growth stocks

Reinvesting dividends can be a viable way of building wealth. But I don’t think it’s always the most efficient – even in a Stocks and Shares ISA.

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There’s no dividend tax to worry about. ISA advantages, however, don’t get you away from stamp duty and transaction costs.

Even with brokers that don’t charge commissions, those can still add up. That’s why I prefer growth stocks for building wealth. 

Reinvesting profits at high rates of return can be a powerful force. And I think the UK has some interesting companies that can do this.

Small-cap growth

Shares of Judges Scientific (LSE:JDG) have fallen 58.33% from their highs. But I think this could be a really compelling time to take a look.

The big challenge recently has been weak research funding in the US. But it looks like things are starting to pick up on that front.

Judges hasn’t reported signs of a recovery yet, but I think it might only be a matter of months. On top of this, the long-term picture is encouraging. 

The firm boosts its organic growth by acquiring other businesses. And its size means it should have a lot of opportunities for growth still ahead.

The road to £1m

Buying businesses can be risky – a bit like investing in the stock market. That’s something to keep in mind with Judges Scientific. 

The best way for investors to do this is by building a diversified portfolio. And investing on a regular basis can be a great way of doing this.

Aiming to become an ISA millionaire takes time. But that means the sooner you get started, the better your chances.

Stephen Wright owns shares in Judges Scientific and Netflix.