Many people are still failing to take full advantage of their ISA tax break, because of confusion over the benefits that the savings vehicles offer.
With the end of the tax year fast approaching, research from Nationwide Building Society found that 95% of those surveyed could not state the correct ISA allowance for the next tax year.
One in five mistakenly stated their cash ISA allowance for the current tax year.
More than a quarter did not think there is a limit on how much they can pay into an ISA each year.
At present, £10,200 is the contribution limit for an ISA overall, with the maximum payable into a cash ISA £5,100.
In the new tax year, the overall ISA limit will rise to £10,680, with the cash ISA limit rising to £5,340.
Extremely worrying was the revelation that nearly two fifths of people thought tax was paid on the interest earned on money in an ISA.
By making full use of their ISA and its tax relief, people can ensure any interest earned will not fall into the hands of the taxman.
"Our research shows that there is still a great deal of confusion and misunderstanding around ISAs, and that people are still not taking full advantage of the tax breaks that they offer," said Robin Bailey, director for savings and investments at the building society.
"We estimate that cash ISAs alone are saving consumers over £680 million in tax a year - clearly a substantial saving.
"What's more, few people are taking advantage of their ISA tax relief by utilising their stocks and shares ISA allowance, and are therefore missing out on the potential for even greater growth on their investments."
Make sure you make the most of your ISA allowance, both in this tax year and the next.
Nationwide currently offers a cracking rate on its e-ISA Cash ISA of 3.10%, while other providers such as Chelsea Building Society and West Bromwich Building Society have some equally fabulous deals available.
If you're a little more adventurous, and want to take full advantage of all your ISA allowance, then equity ISAs come into the equation.
Thousands of investment funds are available through different equity ISAs, ranging from Baillie Gifford's Investment Trust ISA, to Engage Mutual's Stocks & Shares ISA, and the Virgin Climate ISA.
The important thing to remember with an equity ISA is that the value of your contribution could go down, as well as up, making it essential you consider carefully the risks involved before taking the plunge.
Looking for a cash isa - Compare cash isa rates Request a FREE ISA Savings brochure now
Disclaimer: Information is correct as of the date of publication (shown at the top of this article). Any products featured may be withdrawn by their provider or changed at any time.
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