Choosing the wrong stocks and shares ISA or pension provider could cost savers as much as £100,000 over a decade, according to a new comparison by financial education firm Investing Insiders. The analysis, led by founder and managing director Antonia Medlicott, examined the top and bottom performing providers in the UK market, revealing stark differences in returns that grow exponentially over longer investment periods.
The £21,578 gap on a £10,000 ISA
A Stocks and Shares ISA is a tax-free UK investment account that allows individuals to contribute up to £20,000 per tax year into funds, shares, and bonds without paying Income Tax, Capital Gains Tax, or dividend tax on returns. On a £10,000 ISA investment held over ten years, the difference between the best and worst performers amounts to £21,578, a sum that grows significantly over longer timeframes.
Ms Medlicott explained: "Adventurous portfolios offer the highest risk but the highest potential returns, whilst conservative funds offer the opposite." Her analysis found that the strongest ISA performer over ten years belonged to the adventurous category, delivering returns of 224.98 per cent. The weakest sat in the conservative bracket, managing just 9.2 per cent over the same period.
From £10,000 to £32,498 with the top fund
In pound terms, a £10,000 investment placed in the top-performing fund a decade ago would now be worth approximately £32,498. "That's an astronomical difference of £21,578 between the amount of money you would've earned, and that's only over a 10-year period," Ms Medlicott said. "Increase that to 20, or even 30 years, and the distance between the two grows exponentially."
For someone who had diligently built up £50,000 in ISA savings, the top-performing fund would have turned that sum into £162,490 over the same ten-year window. By contrast, placing that identical amount in the worst-performing option would have yielded just £54,600, a difference exceeding £100,000.
Worst fund reduces £50,000 to £705 in five years
Ms Medlicott shared: "This means someone with a £50,000 fund would have increased their pot to £140,140 in the last five years in the best fund, but reduced it to £705 in the worst." The comparison underscores the importance of fund selection when investing in ISAs or pensions, as the choice between adventurous and conservative strategies can have profound financial consequences over time.
