While many savers use Individual Savings Accounts (ISAs) to take advantage of their tax status to boost their personal savings and investments, research from Vanguard UK highlights that, for many investors, the typical fees charged for an ISA often outweigh their tax savings.

For example, a basic rate tax payer invests £5,000 in a UK corporate bond ISA. Assuming an average yield of 4.5 per cent, this investor should benefit from a tax saving of around £45. But, as the average charge on such a fund amounts to over £50 per year, the investor would actually lose more in charges than they’ve gained in tax savings.

If this investor put that £5,000 to work in a low-cost ISA, such as one investing in low cost index tracker funds, the cost of doing so could be as little as £10. Therefore, the investor would get to keep over 75 per cent of their tax relief.
 
A higher rate tax payer would also benefit from a low-cost approach. For example, £10,000 invested into an equity growth ISA would achieve an income tax saving of around £50 per year –assuming an average yield of 2 per cent. The costs of going down this route are much higher, typically over £150 per year for an active fund. So the investor stands to lose three times what they’ve gained in tax relief. Again, a low-cost ISA could cost £20 a year and therefore the investor would get to keep around £130 more per year. Even before compounding, that could amount to £1,300 over 10 years.
 
Tom Rampulla, managing director of Vanguard UK, said, 'Costs matter. For many investors, charges on their ISA outweigh the tax savings. By choosing low cost funds, such as index trackers within your ISA, investors can keep more of their tax relief, which is after all the reason that we have ISAs. Whilst the annual savings outlined above may not seem huge, it soon adds up over the years and can make a significant difference to your return.'