When asked about their plans for the tax-free wrapper, 44 per cent of 813 voters said they weren’t going to use all of their allowance, while 15 per cent said they wouldn’t use up any of it.
Just over 10 per cent of respondents said they would be investing most of their £11,280 allowance for 2012-13, while 18 per cent said they would invest some of it.
"Unlike a pension there is an opportunity window for using up your allowance – it’s use it or lose it. We encourage people to use up as much of both their stocks and shares and their cash ISA as they can," the Tax Incentivised Savings Association’s director of policy Malcolm Small said.
He added: "It’s not a surprise to see nearly one in five not using up their ISA allowance. With below-inflation pay rises, and even pay cuts, the pips are really squeaking."
The response shows a shift in sentiment from a poll in September last year asking if investors had made full use of their ISA allowance yet.
Of 652 respondents, 42.6 per cent said they had done so, 34.4 per cent replied that they had not, but intended to, while 23 per cent said they did not intend to.
A poll at the end of last year indicated 57.2 per cent of 657 investors had their entire ISA in stocks and shares, 15.5 per cent held it in cash, while 27.3 per cent used a mixture of both.
Another questionnaire of FE Trustnet users late last year suggested that 15.8 per cent of 435 investors were planning on sticking to cash in the coming year, 49 per cent would put their allowance into equity funds, while just 9 per cent were planning on piling in to fixed interest vehicles. The remainder said they would use either multi-asset funds or single equities.